It is a little hard to tell what is missing.
Obviously the carb and plumbing are missing.
I can't tell if it has a piston and connecting rod.
Missing items will definitely affect the price, but the basics seem to be there, ie: the side shaft, gears, valves, etc.
If the piston and rod are included, just about any carb would work.
I am not sure about the gearbox.
It may or may not be missing some critical parts.
Based on the 5hp engine Jason posted, this engine may not go for very much.
(All the more reason to buy it, LOL).
If the piston and valves are all free and working, then restoration would be pretty simple in my opinion, but it would take some TLC to get it right.
It sort of looks like it has had a frozen water jacket crack repair job.
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