610 - as far as frames go that are NOT so stringent with track geometry, you can check out the Steamroller. Other options would be an IRO too. What you might want to do is surf through here: http://bikeforums.net/showthread.php?t=225713 to try and find something above and beyond the great lengths dutret has taken to assist you. I am sure it will prove more useful, too.

Yojimbo's has a great selection and unparalleled service - definitely a wise choice!

dutret - please post pictures of your bike in the appropriate thread from now on.