Engines, yum. 
Not a lot of free agent engines available.
We looked at Weber engines out of Germany last year for running marine systems, jetpack pumps. The engines used in Polaris snowmobiles, something like a couple hundred thousand in service if I remember right. It would be cool if an American made engine could compete in this space.
The turbocharged two cylinder at 104 HP was interesting and about 6 grand as I rememeber.
V4 Engine: http://www.weber-motor.com/en/products/mpe-v4/technical-data/index.html
Ray, love those illustrations, thanks for that link. When I was in high school that style of drawing was as good as it gets, still wish I could draw like that. The clarity of communication in that kind of illustration is hard to beat.