Original P slot centre caps

Hi everyone, not been on here in a while, mainly been waiting for my gti to come back from the bodyshop, which it has! (pics in project section to follow)

Anyway, one of my best mates has a mk1 gti and i am now in need of a set of p slots for mine.  He has a few sets of them and i picked up four yesterday along with a set of original centre caps with the raised pirelli logo on them - all in need of a refurb but in decent condition.

Its always difficult dealing with best mates and money, he just said 'we will sort something out at some point mate' but I want to be fair to him and give him the right price for all of it.

What sort of money are they worth?

Thanks in advance