Possible oil pump failure - how bad is it?

[richhath]

I think my oil pump is knackered on my 1.6Turbo diesel engine. The buzzer of doom came on last Friday so we didnt go away in the van. When I came back I decided to check the oil, its been about a year since the last filter change so I dumped the oil and changed the filter. When I started the engine it ran for about 2 minutes then cut out. I checked the new filter and no oil had got into it. So I think the pump is knackered.
After a few chats with various garages there was alot of air being sucked through teeth, so I am expecting the worse, but I cant get the van off my drive to a garage.
Does anyone know how big a job this is? I think the sump will have to come off to investigate/fix? Could there be an alternative problem (grasping at straws) How bad is this likely to be, could the engine already be knackered?
I'm trying to remain calm and imagine a brighter world, but I can see some cracks!

[Oldiebut goodie]

I fill the oil filter with oil before fitting - can get messy but gives the engine a fighting chance.

[kevtherev]

Yes fill the filter first
Then have the oil pressure checked with a wet gauge
I doubt the oil pump is fubar yet

[richhath]

Thanks guys for your replies. I'll try filling the filter at the weekend and see if it helps recover the engine.