I have two GSO Crayford focussers for sale. They carry the Bintel brand and have come off Bintel reflectors. Both are in good working condition. I cannot exactly recall the tube diameter, but I think both came off 8" reflectors. I have held both to my Bintel 12" tube and the gap is not excessive. Of course, the base plate can be changed for one with the correct radius for the tube - two grub screws hold it on.
10:1 focusser - $90 plus postage Sold thanks
1:1 focusser - No longer $70 plus postage Now $50 plus postage (the 1:1 lends itself well to attaching a motor drive to the shaft.) SOLD!!
Whichever purchaser of a focusser wants it, I will add the 2"--> 1.25" adapter for an extra $5. Sold thanks