Do it, you might even get lucky and be able to re-use the spokes if the rim you get is the same ERD as the original steel rims. I know on Raleigh Sports wheels if you replace the originals with CR18 rims they are close enough to do a simple tape-together and swap spokes over "wheel-build." If the nipples are in bad shape just buy new ones. Many LBS's will sell you nipples for about a nickle a piece. 72 nipples isn't a big price.