I am in the market for a snowblower and thought about repowering a used unit if I could get it cheap enough and without spending too much time on it. So, I am looking for suggestions of those brand/age snowblowers that are close to a drop-in without too much modification.

For instance, after doing some research I found that some of the blowers have an extra PTO shaft off the cam rather than a single or dual belt off the crank. Since these engine types are not available, I would not want to spend the time for the modification Changing pulleys, sleeving and re-drilling mounting holes are OK.

 

briggs may still offer the dual shaft engine as they are used on tillers. Someone on a forum somewhere had one which I think was new. There are some blowers that drive both wheels and auger off a double pulley on the crank pto shaft. although I just viewed a site with a wack of briggs and no dual shaft ones but here is one on CL
8.5HP Briggs Dual Horizontal Shaft Engine New in the Box

Note the ad says it's 8.5 HP but it's really about 4.5 hp. which is about right for a 12 series. the torque is 8.5 and 8.5*3600/5280= about 4.5

 

Do some searching on the web. Replacement engines are available including ones with auxiliary PTO shafts.