The camper conversion you have is by RGA CONVERSIONS OF NORWICH.
Roger gordon anderson (RGA) is a independent motorhome conversion centre from small vans to large trucks but mainly built on the vw bay T2 and vw T25, the HUNTSMAN being the most common conversion, all campers were built to specification order or to individual requirements.
The furniture was known for it's quality craftsmanship and durability being made from formica faced plywood with aluminium angle on all corner edges, the sink, the elevating roof, the water tank and louvre window unit were made by SUPERVISTA MOULDINGS that were an RGA associated company they also made a fixed roof high top that looked like a huntsman boat stuck on the roof.
The company started off as RGA CONVERSIONS, MOTOR CARAVANETTE CENTRE, OLD COSTESSEY, NORWICH NR8 5AG in the 1970's then became HUNTSMAN MOTOR CARAVETTE CONVERSION CENTRE 28 WEST END COSTESSEY NORWICH NR8 5AG in the 1980's and now trade as WENSUM MOTOR CO from the same address now a vehicle repairer and commercial vehicle bodybuilders(coachwork) company , i think they still fit and repair pop/high top roofs.
On the sides of your roof in the middle of them two horizontal triangular lines it should have the letters/motif of R.G.A and also R.G.A OF NORWICH on the window unit and R.G.A letters/motif on the sink.
Roger would be about 84 now and i'am told he like's to see his old vans, so if in norwich give him a look.