Try Certified Parts, located in Janesville, Wisconsin. They bought up the Tecumseh small engine inventory last winter, and they are in the process of marketing and supplying these parts to the aftermarket.

Can you give me a link that shows what Tecumseh parts they have? I went to their website, but no mention of lawnmower parts that I could find. I do not have an exploded drawing or parts listing for the engine, so not sure how I would even start with what I have now.

Sorry, I don't have the link that you need, nor do I have a parts list for your engine. Here is what I know: Tecumseh was building small engines in several Wisconsin towns, over a period of roughly 70 years. They had several thousand employees. A few years ago, they set up a small engine plant in Brazil, and they began to downsize the Wisconsin operations. Next, they closed one of the Wisconsin factories altogether, and last year, they closed the remaining factory in Wisconsin, and announced that they were getting out of the small engine business. Certified Parts made a public statement that they were purchasing all of the Tecumseh small engine inventory, plus the tooling, plus the drawings. They also stated that they would begin manufacturing parts for the small engine repair market, and they raised the possibility that they might put some of the Tecumseh engines back into production. This was back in December 2008, I think.

If you have 5#s of compression, pop the head and see what you've got. Maybe just a pinch of ? between the seat and valve. You would never correctly rebuild that engine cost effectively. Places such as Small Engine Warehouse on the web have replacements ~ $150