Starter Motor for 350 Chevy

Has anyone ever replaced the starter motor or know what was used on the 350 Chevy motors? Mine went out and the starter looks like a small high torque type with a 1" thick aluminum adapter plate on it. It definitely isn't a standard Chevy one, I am thinking it might be off of an import like a Nissan or something.

Not real sure but sounds like a high torque mini starter. Used for tight location or high compression engines.