Stay with 2 stroke for ease of maintinence and less weight. Any mid 90s or newer merc, yammie, or johnson/rude would be great. You are correct, John/rude is now Bombardier (and that is not necessarily a bad thing). I would go with yammie if you can.....quiet, efficient, and reliable, but parts are more expensive.
Good luck
1986 Honda ATC 200 S
Some quads and a S x S
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