Graham
You have referenced an earlier catalogue than the one I mentioned in post #11. What is particularly interesting, specifically because of the 400 and the D115, is that your extract mentions that for an extra 30 shillings (per dozen) you can have a rosewood handle. Also this No.171 comes with a metal guard beneath the handle. (as you said) The "A" suffix in Simonds saws denoted a brass guard, but in S & J speak I means no brass guard. Saw plates up to 40" long!
I may have done the maths wrong, but I make the new price $43.85. Either way it was approaching the 400 in cost. Made from vanadium steel? Perhaps Rob Streeper would have some information on whether it would have been a desirable saw steel. Would it account for softness?
Thanks for digging up that information.
Regards
Paul