The ebay listing you used as an estimate for your Leaf Ruth,
http://www.ebay.com/itm/1948-Leaf-Ba...item43b52d7b26, was either a fluke, a rare variation of sorts (collectors of this set see and comment on odd variations), or the result of weird bidding. A PSA 1 Ruth, especially with a mark qualifier, is a 300.00 card at most (unless it's ex-mt with a pin hole or something). Your card is nicer than 300.00, but with the marking on back, it's no more than a 500.00 card IMO. I've been watching prices on the Leaf Ruth for several years. At one time, I owned a very nice PSA 2, without a qualifier, and sold it for 475.00 in buy it now format. Again, it was a 2, but it was one of those nice 2's that makes one wonder how it got that grade to start with.
Having said that, you have a nice card there and I wish you the best of luck.