The chainset is dated 1981 (although it is a GS not an SR). I have Falcon dealers price lists dated 1 April 1980, 25 June 1980, 15 September 1980 and 5 January 1981. The first three have a San Remo section and none of the four have model 76 on offer. I also have what I think is a 1982 catalogue (the one with the Vigorelli in it) and also the 1983 Elswick Falcon catalogue and neither of them show the 76 either. The last dealers price lists I have with it in are the 1979 Coventry Eagle one and a 9 November 1979 Falcon one.I would say you are probably about right for the date of the bike, as the seller did send me some detailed pictures when it was up for sale. You can probably get a date code off the Gran Sport chainset?
Interestingly the chrome seems to extend a long way along the top tube under the paint?
Good idea to keep it as original as possible.
I have publications that show the 76 for for sale in 80, 82 and 83. Also an early eighties brochure picture of one. How difficult they would have been to get is another matter lol
Can you offer any help? Maybe need to discuss offline?