Beautiful Bike Steve, think I speak for everyone here in saying we feel for you, a hard decision to make but in the circumstances understandable and correct.
Having made the decision you now have to maximize your return, my one suggestion would be to change the fuel tank, the present tank would sell so offsetting the purchase of a RGS tank with those iconic big badges which would be more than covered in an increased asking price.
As for a price the Goldie and RGS lads here will have a much better idea than I - good luck with it