Yes, that is the type of pump you need to use with the 3-bolt cams. There's a couple cheaper versions, which are probably just as good, like this (where they even mention the aftermarket cams being all 3-bolt):
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People latch onto brand names, and without hands-on experience with alternatives that's wise enough, but an oil pump like this isn't any kind of precision-machined piece, it's very simple, easy to machine accurately, and Schadek isn't any better than most lower-priced alternatives, sometimes not even as good. When everyone on the interwebs says a certain brand is "the only one to use", you have to remember that literally 99% of them are simply parroting and have never had the thing in hand and wouldn't know how to make a credible comparison if they did. This also goes for the China-bashing crowd, in that case it's 100% parroting because, although I have no love of China (I've been there), they produce everything from the best to the worst of whatever item it is you're looking for. If you'll be buying the same thing repeatedly (Ian), it's worth getting the cheaper alternatives in hand to see if they measure up, they usually do in the case of oil pumps since there's so little to them.
Details that vary are the inlet/outlet hole size, so you want to make sure they are as large as the galley holes they need to match up with. The wear area in the pump body is the upper bore for the driven gear shaft, so the longer that bored bearing area is, the better. Excluding scoring caused by debris sucked up from the sump, wear of the upper gear housing will only occur with wear in the shaft bearing bore; you will almost never see appreciable wear of the lower gear and pin. I use a cheap pump made in India, $20 each, the machining is just as accurate as Schadek's, but its casting has a longer nose for the shaft bore, so a considerably longer bearing area for the driven gear shaft, and that by itself makes it preferable to a Schadek, besides costing much less.
You're going to blueprint any pump you use anyway, that's a must. Apart from optional mods like o-ring grooves, there isn't a lot to do to an oil pump. Blueprinting includes:
checking that the gears mesh and run true without binding
no excessive clearance within their housings (using feeler gauge not more than .003" radial clearance betw. tooth and housing bore)
the driven gear shaft is a good fit in its bearing bore (no palpable sideplay)
the pump body face and the cover are both flat
and correcting either gear length or the body face so that the gear endplay with the cover fitted is .002-.003".
Where I always see people getting into trouble is believing that there
must be a gasket between pump and cover, so they may have a pump with .003" gear endplay when they check with a straightedge or the plain cover, then they put the thin paper gasket in, which is actually .004" thick, ending up with .007" effective gear endplay, and watch their oil pressure go south as soon as the oil gets to temp. Some of the gasket sets have cover gaskets that are over .012" thick (OMG!!), to use that the gears would have to be .009" proud of the housing! Obviously you would not use such a gasket. Whether you use a gasket or not depends on what the effective endplay will be when assembled, use your brain to come up with the right combination.
Too much endplay or too much free radial clearance between gear teeth and housing results in excessive "slip", or oil escaping back thru those clearances from the pressure side to the suction side. Since oil viscosity falls with higher temperature, the rate of slip increases with heat and this can radically reduce pump efficiency. You can't do anything about tooth-to-housing clearance, that's fixed in the sizing of the gears and boring of the gear housings, but you can fix the gear endplay to control slip between the gear ends and the cover, which is where almost half of slip occurs.
If you look it up, a spur-gear pump like this is classed as a positive-displacement pump, but I say any pump that depends on the viscosity of the fluid it is handling to effect a seal between moving elements, and that thereby loses pumping efficiency when the fluid viscosity decreases, is not positive-displacement. I deal with a lot of pumps, not just engine components, and in my book to be positive displacement, a pump has to move the same volume of fluid on every cycle, regardless of fluid viscosity; that leaves only piston and diaphragm pumps as positive displacement. Why am I going on about this? Because it helps to understand pump dynamics and the role of slip in a non-PD pump so you can do things to minimise it in order to retain pump efficiency when the oil gets hot.
