I am selling the 2.7" focuser from my Jaegers 6" F8 refractor. The backplate & focuser housing are cast as one piece and are made to fit into an approx 6 7/8" inner diameter tube.
These focusers were never engineering masterpieces, and backlash was always a given. Smooth is not a word that I've ever heard used to describe their focusers. But they were an inexpensive bolt on backplate/large format focuser available to the amateur on a budget.