Small bodywork repairs - Advice needed

[F1uff]

I've got a few areas on my van where I need to do some tidying up - Small rust spots around water filler port, on tail gate where bike rack has bitten into paint, and 2 little spots underneath gutters at rear

Want to clean these spots back to rust-free metal, and then touch up with small brush.

I don't wanna be using aerosols for these areas as they are too small (and mainly gonna be out of sight behind bikerack/closed tailgate)

Have ordered 250ml of cellulose paint. Just not sure what to put underneath. I don't wanna use red oxide as this is gonna give me a pinkish finish. I'd like to get my hands on small volume of white primer (that I can use a cellulose top coat on). Does anyone know where I can get this from? (Local paint supplier unable to help and internet searches not coming up with much.)

Halfords do red oxide primer, black primer and grey primer (a possibility???) in 250ml pots for ~£4 but unfortunately/frustratingly don't do a white one.

Again, since the areas are pretty small, I wasn't planning on using an etch primer. Do the experts out there think I will be OK with a regular primer onto metal (for small areas) or should I use an etch primer first? Seems overkill for such little jobs.

I'm just trying to avoid ending up with litres and litres of primers and paints for what is a few small areas.

Alternatively - would I be better just removing loose rust, painting with Kurust and then overcoating with cellulose paint? Can you use cellulose paint over Kurust?

Any assistance greatly appreciated.

Fluff

[eatcustard]

Use U-POL Zinc 182 Primer (in Grey)
yes you can paint over Kurust, but I would use a primer first

[Bert2]

Since you have the paint, why not get a humbrol airbrush and put it on with that, you will get an almost perfect match as long as you have the correct paint, I have used these many time for scratches, they produce no over spray use very little paint and they are just like using a pen. You can pick one up for around £11 and the propellant costs about £3 one can will do it, the produce so little over spray you don't even need to mask off large areas far better than using a brush for small areas. For the under coat I used to use was Halfords spray can light grey under coat the bottles supplied are small so you can spray the paint into them and use the air brush to put it on accurately give it a go practice on a piece of card first to see how large to set the spray pattern goes from about the size of a 20p to the thickness of a pen line.