That is a good price for a serviceable boat. They were probably just happy to get it off of their lot and the $300 was just gravy on top.
I did not see an outboard (or mount) but maybe you wont really need that for the lake you intend to sail on (which lake? where?).
It has an outboard mount on the port side. I didn't take pictures from that side due to the fact that it was next to an old camper, and I couldn't find a decent angle. I'll post more pics later.
The Mac 22' still has a pretty good following and is a much better trailer sailor then the much maligned Mac 26' 50HP motor sailors.
Full disclosure: I have never sailed on a Mac 22' I just know that there are quite a few sailors out there enjoying these older MacGregor trailer sailors. I have sailed on a Mac 26' S and while the rigging struck me as being a bit light it did handle well and has a lot of room down below.
Thanks! I'm looking forward to getting it on the water yet this year.