Robert, check on ebay for rifle scopes. I've bought several old vintage Mossberg and Weaver scopes there - good prices with a decent seller. Often they offer the older steel tube scopes, in 3/4" and 7/8" diameter that were popular before they all standardized on the one inch tube.
I don't know if these rifles ever had a particular brand of scope - I just go with something that 'looks right'.
Get the mount, and see what tube size it requires.
I love those old scopes - they generally have the fine crosshairs I like, instead of the newer 'duplex' style that isn't as good for precision shooting.
PROUD TEA PARTY EXTREMIST!