Tyler, I know of two solutions: find some original stock boots (difficult but not impossible) or make a set of adapters out of 4″ ABS sewer pipe and use modern boots from a 4×4 GMC truck. I’ve done both, the former most recently. The Kent CV’s were not made by Cortez but were a power plant item from some sort of heavy equipment, maybe agriculture or industrial. My memory may be incorrect here but I recall “DAVCO” as the manufacturer ( I can check a spare CV I have stored). Anyway, I’d check with a farm or industrial equipment parts house and take them an old boot and see if they can match it up. On the new GMC boots, one of my good buddies with an engine lathe glued a short piece of 4″ ABS sewer pipe into a 4″ coupling and trimmd it down and it worked great. I used then in my old 1972 rear bath and they have been going strong for over 50,000 miles. I can post pictures of the adapters it you have access to a lathe as well as the GMC boot part number. These boots are readily available at any parts outlet like O’Reilly’s, Autozone or RockAuto.
Jess Bressi, OC CA
1974 Side Bath/Rear Bedroom
19.5" Rims/front disc brakes/3.71 Final drive
Keep on Cortezz'n