Can you take a picture looking down on it? Is it some sort of pulley?
That looks like a collection of parts. A shaft with one or more snap ring grooves, bearings and a shaft collar.
Shaft possible
https://www.mcmaster.com/product/5930N135
It is a Doo-Hickie.. it was made on a Lathe and a Bridgeport. Did you get a passing grade?? ;0)
Looks like a shaft flange with a dowel put into it. I doubt it's sold as a complete assembly with that "axle"in it.
Looks like something for automation... a track dolly for a servo motor? Gantry wheel flange?
Check Misumi. Search "mounted bearing"
I agree, not going to be sold as that assembly, but absolutely could be put together with 100% "off the shelf" components.
Got any pics of the timing belt pulley?