Jacob,
The VMCC Machine Register is not particularly helpful but your machine would appear to be earlier than 1935. Possibly 1932 or '33. I don't know Sunbeams but suggest that you do a search on the Net for a Club, or whatever. Somewhere I have the latest list of VMCC Marque Specialists can't locate it right now. (My specialisation is Triumph)
Regards, Peter C.