Weaver 82 scope base fits the modern Handi barrels. If you have a scope with a bell you will need pretty high rings but the hammer clearance kind of comes into play as well on the higher rings. Some people use a 4x shotgun scope (longer eye relief) and mount it just ahead of the hammer so you don't need a spur and also can go lower to the barrel.
I believe I have a Weaver 82 on my old topper 58 as well but I didn't check before typing this so that could be wrong, (Just checked it is an 82) but the FAQ will list what you need. Hope this helps, thejanitor