For some values of Beogram and Beomaster, certainly yes.
The first obvious issue is the RIAA preamps or lack of them. I don't think there ever was any Beomaster with two preamp'd phono inputs, so at least one of your Beograms should have it built-in (or you need an external preamp). The other can then go to the other phono input (for some old Beomasters) or you can pick a free TAPE or AUX input for it.
The second issue is remote control. I don't know what happens if you have two sources of the same kind connected via Datalink to a single Beomaster. But in any case you should be able to unscrew the datalink pins from one of the Beograms and use it as a "dumb" source.
-mika