This is pretty difficult to find these days, and frankly, there is no way to find those owners. Not sure what the market is like in your area, but in many parts of the country, the market has recovered quite nicely, and we are in a pretty good seller's market. That means more buyers than sellers. Most sellers would rather SELL to a viable buyer, instead of renting to someone who may or may not actually qualify for a regular mortgage when the term of the contract is up.
I would talk to a couple of lenders to see what you can do to get your score up. It could be as simple as paying down, or paying off a couple of accounts.
I'd continue renting and working on your credit. Maybe you can stay where you are, and rent on a month to month basis? Or sign a 6 month lease? Good luck!