That looks like a generic PC clone. You'll have to open the case to see what's inside. It could be anything from a 4.77MHz XT to an early 386, based on the case design.
However, if I was a betting man, I'd say it's likely to be an 8MHz XT from the mid 80s. And even if just that monitor works, you got a steal at $10. CGA monitors are hard to come by, and if you can get that computer working, it'll be a nice machine for playing around with DOS games, BASIC, and 8086 assembly language.
And just so you know... if that's a 286 or newer, you can use a PS/2 compatible keyboard - you just need a DIN to PS/2 adapter. If that's an XT class machine, you'll need an XT keyboard. XT and AT keyboards use the same 5-pin DIN connector, but they carry different signals.
That is the cloniest clone I have ever seen. It is so extremely close to the original, all it seemingly lacks is the square IBM badges. Weird how these companies were able to get away with so closely duplicating IBM's case shape without the massive IBM suing their pants off.....
Imagine buying a Macbook clone that looks exactly like the laptop except it has a banana logo on it. Apple's lawyers would be foaming at the mouth.
(Hmm, I also see an antique computer, electronics, and machinist hobbyist...)