Update: All of the projectors are now in the cafe.
Correction to the lenses:
1x Kodak VARIO-RETINAR S-AV 1000 75-120mm, aperture not marked but probably f/3.5, screw focus.
1x Docter VARIO-DOCTARLUX 70-120mm f/3.5 MC, rack focus.
Either will fit in any of the projectors.
The Docter is probably optically the best. I've cleaned all the elements inside and out, and have put it in the Ektapro 4010. Do note however that the zoom ring on the front is loose. When turning it keep it pushed in towards the body, watch the zoom group moving inside, and make sure you don't try to move it beyond its range or you'll have to put it back together again (easy but annoying).
Graeme, none of these have timers but they all have cable remote sockets so we can plug one in easily enough (and it can be a simple homebuilt 555 circuit). The S-AV 1030 has a remote, but this doesn't fit the Ektapros.
Note that the Ektapros have a much, much more even light distribution than the S-AV model as well as being 50W brighter.