53 starter motor question

[Chester Leighton]

I inherited a 37 Ford pickup from my father. It has a 53 8BA engine, 5 speed transmission and open drive shaft conversion. It has been converted to 12 Volt electrical. The starter has been having bendix issues since Dad first got it. I've put two on it in 5000 miles since I've had it. When I got it, there was no support bracket at the rear of the starter motor, do I bought one. When I went to install it, the hole in the bracket was about an inch away from the oil pan bolt hole it should have bolted to. I also noticed that the face of the counterweight /collar on the bendix gear that faces the flywheel looked like it had been rubbing on the flywheel and it sure sounds like it does when cranking. The starter motor isn't original. Is it possible that there are two different length starters and I have a starter motor that has too short a shaft and body? If so, what is the correct motor and where can I get one?