Re: 15 hp chrysler
It's hard to find any running 15hp for that kind of money. Certainly you won't find an 80s vintage johnnyrude 15hp for anything near it.
Are Chryslers great outboards? Nope. Are parts sometimes hard to come by? Yup. But...parts are available...you just won't get them at the local marina. Common stuff, like impellers aren't at all hard to come by.
If you can find a nice 80s Johnnyrude for anything like that money, snatch it up. However, if this 15hp really does run well, pumps water, and starts easily, it's just $275. Around Minnesota, you'd pay more for it.
That said, you should consider it a temporary outboard. It may last a year or five, but eventually, you'll dump it for something better.