More than likely, yes. Assuming it's how it came from the factory. There's nothing to say that someone didn't add a motor to a former hand crank, etc. If it has a solid wheel (not spoked) it's likely original and a 15-90.
The thing about the gear drives is that one of the gears isn't easy to get, and it's fiber, so it can get brittle with age (if not lubed properly often enough, etc) and can break. With a belted one, the belt slips first.
I personally will take either, and have both. I have a 201-3 and a 201-2, the same differences - the -3 is belted and the -2 is the potted motor. Functionally, for my purposes, there are no differences, but the motor on the belted one is a smidge easier to take care of. (Wait til you have to turn the machine on its front to lube the worm gear on the potted motor. Ugh. Yeah, I'm a wimp.
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