I know you don't want to throw money at this thing, but if you are not ready to try rebuilding your starter yourself you might consider getting one at a parts store. That way at least you would know the starter is good. You should be able to pick one up for about $60.00
With a good battery, good cables, a good starter and good connections, that engine should turn over great. If it doesn't, then you will know there is something physically slowing the rotation of the engine.
