These are brand new. I just bolted these up and decided to go another route. The mounts are from ATC, I will link below. The mount was $110. I am including pulleys with bearings. Shoulder bolts cost $40 and bearings were $20. I also 3D printed roller sleeves which I am including. Asking only $90 shipped.
Please let me know if you have any questions. You can also see from my build thread that the board is not even complete yet, which means these mounts were just bolted up.