A picture and engine mileage would be much more helpful. Anyhow, I'm not sure about market value but I think that it shouldn't be over 20k-25k considering CD200 were sold from early to mid 80's and you're basically looking at a roughly 30 years old bike that needs some work which might cost you another 10-15k.
My advise, forget Roadmasters all together and opt for a Suzuki GS500. I've seen several army auctioned (1988-1992) GS500E selling for little over 100k. Trust me, A GS is MILES better ride then a Roadmaster both quality and performance wise as it makes 50BHP compared to Roadmaster's 16BHP. Not to mention GS's spare parts are readily available.
Spend some more and get a much better bike...
Up to you.