Brian,
I didn't see your comment on the brass around the seat-stay area. Brass would suggest a 531 frameset, but a weight of 1700 grams, if accurate, definitely suggests 753 tubing.
I'm assuming your bike has drillium dropouts, which came out at about the same time as 753 tubing? The first reynolds 753 frame imported to the USA (SB497) was shown on ebay recently.
http://cgi.ebay.co.uk/
Dale, can you capture some of these pictures for the CR website ?? The serial number and provenance are pretty important in raleigh / reynolds history.
When reynolds 753 was introduced, I know production at Ilkeston went into overdrive, perhaps annual output doubled in the ensuing 5 years (I'll talk to Mike Mullet to get the definitive answer on this ...)
- Don Gillies
San Diego, CA