I would look at something like a 56 mag 2 or a 051.
The 056 and 051 are good saws but at this point old. I think the op has better options out there instead of selling 1 old saw for another old saw. If that was the case then he should just keep the 8500. For a 600 budget you should be able to find a nice 9010,066,385/390/395, 7900