I paid $200 (IIRC) for a used Rollei 66P projector a couple of years ago.
And I was given a Kindermann medium format projector a month or so ago.
I don't know of anyone who will mount the slides for you.
There is some old stock of mounts available on store shelves, but it isn't inexpensive.
I have both GEPE mounts and a mounting tool as well, but I really need to set off some time for a slide mounting binge.