Upgrading old Campag groupset with modern parts

The wheel is campag chorus with ambrosio elite prisma rims, the rims appear to be thinner than open pro when I put that wheel on to see the tyres clearance on the frame/fork (with 28mm).

quick question, Open pro is the best option for a skinny lightweight rims or are there better option?

Open Pros are very good rims and easy to get hold of. Personally I like Ambrosio Excellence rims, they are a little bit heavier than Open Pros but aesthetically look the mutts nuts.