I suspect your bike might have a 126mm hub spacing at the rear, so that might limit your choice of new, off the shelf wheelsets, as wheels had moved over to at least 130mm spacing since the 90's. Bulding new wheels from NOS parts will cost quite a bit of money if you want to come up with very light wheels. I think the most cost effective way to replace your wheels would be to find used ones in good condition either at CL or eBay. It might give you a better chance to get higher quality/lighter wheels without spending too much.

Chombi