Well..... I would ask some other questions, but being you already took it apart, it's too late. I'd say slap some rings in it... If it doesn't fix it at least you can rule that out.
BUT, if you do re-ring it, hone the cylinder so it will seat the rings.
Since you have the head off and the motor apart, might not be a bad idea to go ahead and take the valves out and check them too. They aren't stuck are they? How do the seats/ valve faces look?
