All 265s are essentially the same. The reason he advises to use the earlier version is because of the mechanical speedo drive. '85 is the last year of the 265, and those cars got the speedo signal off of the differential(electric) and the mech speedo drive on the trans was closed off. If the only trans that you come across is from an '85, the speedo drive can be added. It's just easier to use a 265 that came already outfitted.
They are out there if you're patient. Just put a wanted post in the parts section in a few boards. I know someone who has one available if you can't find one.
Put your location in your wanted ad so local people can chime in. They're heavy, so shipping will add to your costs significantly.