Rebuild the engine that's in it. It looks like it fits the machine very well. You might have $100 tops wrapped up in rebuilding it. I like to use NOS parts when I can find them.
Check Ebay for NOS rings,connecting rod,gasket kit and carb rebuild kit. Those old briggs engines run forever. It probably has a 1" diameter crank. You will have a hard time finding a push mower engine with a 1" crank.
STD Rings Briggs and Stratton 298174 A bunch to choose from. $4-$27 for a set.
NOS STD Briggs & Stratton Connecting Rod 297568 $18 shipped
Carb Kit $7.25 shipped
Points and condenser. You can probably find a NOS kit for around the same money but the condensers do not keep well with age so I suggest getting a fresh 1. $12.99 shipped
Edited by EricFromPa, February 17, 2020 - 06:48 PM.