I don't see why you couldn't do it so long as it bolts up and you can hook up the drivetrain. I've never done such a swap, but there isn't much the whole drivetrain of a snow blower.

The length, diameter, amd height of the engine output shaft would probably be your most crtical concerns. You will probably find that the Tecumseh engine bolts right up to the mount plate.

There is a whole series of Craftman exclusive Tecumsehs that have two pullies on the front of the block, one off the cam, and one off the crank. I have a really nice Crapman snowblower that has this engine so I can post pics if need be. The only problem is the motor is shot and a replacment is so rare the machine has sit for years. (I found it in the garbage)
My point, make sure it's not one of these stupid things.