I would believe it is possible with a BeoMaster that has an MCL connection. You can then use a BLC (BeoLink Converter NL/ML) to link to the BeoSound stage.
It would be quite a chain:
BeoGram 8002 – (optionally pre-amp with datalink) – BeoMaster – Converter 1611 MCL/ML – BeoLink Converter NL/ML – BeoSound Stage
With a BeoMaster with built in pre-amp (some BeoMaster 4500s have that), you could skip a box (I am not sure if more recent BeoSounds that have a MasterLink connection can control BeoGrams through their AUX sockets). It will also require some persistence to program the BLC. But unless I oversee something I believe it could work.
They are only available second hand. In the Netherlands they go for 200-300 euro.