I have a GR-2 Deluxe alt-az single arm mount for sale. Also have the APM wood tripod which works with it. Both mount and tripod are nice and sturdy and in excellent condition. I can email pictures.
GR-2 Deluxe mount: $260 + shipping
Tripod: $260 + shipping
Both together: $500 + $30 shipped in CONUS
Note: the mount includes the optional counterweight shaft