Part of the problem is that there seem to have been a fair number of carburators used on each model. Trying to match something up can be frustrating, as no doubt you have found out!
I worked with the local AGCO dealer to match up a carb kit that would match up with my old HP 70 . It was a struggle.. but we got it. If the gasket doesn't match, but sorta works, just be certain that no holes on the upper or lower halves are covered by the gasket. You may have to cut/puncture the gasket.
   The other option is to make your own gasket.... it really is not difficult, it can be done with a good exacto-knife.
                               Cal