Kohler 7hp K161S, Serial No. 536691, Spec No. 28542E. This was removed from an Original. Seems to run good but has a little puff of smoke at initial rev. This could be from the timing being off, or the carb out of adjustment or just dirty. I picked this engine up after it was removed from tractor and had been sitting 3+ years. It had no spark. I installed points (set at .020) condensor and coil, and got spark - added gas, connected part of the wiring harness, and it RUNS pretty good.
$200 plus shipping gets you everything in the pics except the coil, points and condensor (I used these off another tractor). That means you get the engine with oil pan and head, carb, basket pulley, gas tank and saddle, S/G (which is old original style with solid pulley and both end caps are cast iron), volt regulator, and wiring harness that looks in pretty good condition. The pulley and grass screen is missing on the flywheel side.
Or, $125 plus shipping gets you the basic engine with the oil pan and head, flywheel and shroud, and the other basic tin work on the engine. If you want any of the other items (carb, gas tank and saddle, basket pulley, S/G with mount, wiring harness, volt regulator) - I'm open for discussions.
Pics below are not the best. I can send a short video of it running if you send me an e-mail.