Au contraire, my friend.
When we restored my son's '74 Dart Sport, we bought the replacement rubber bushings at a local auto parts store - can't remember which one.
The rubber is encased in a metal sleeve, and the old one takes a bit of encouragement, but it will come out.
An engine mount has holes in both sides that the bushing slides through and the metal sleeve was punched in a couple of spots to splay the sleeve's edge out enough to hold it in place. You have to straighten out the punched spots for the bushing to slip out of the engine mount. The new bushing/sleeve is then driven through the engine mount holes and punched with a cold chisel to recreate the splayed spots on the edges.
Try checking with Car Quest, AutoZone, Advance Auto, O'Reilly, or NAPA. It had to be one of those - that's where we got all the parts for our project.
Jerry