Thanks!
I was not expecting a reply within 24 hours (or even a week, if truth be told.)
A creative google search (you aren't the only one) brought me to the same series of locomotives only 3 minutes ago - how time flies...
While this certainly narrows it down, be careful of assuming that the builder and the purchaser followed the same sequence in their numbering.
The series starts at 69814 on the Alco list, and runs 941-947 on the New Haven locomotive roster, but sometimes an engine would be delivered from the builder "out of sequence" which was no big deal for the railroad - they didn't care if 944 was pulling cars before 943 so long as the cars were moved - but it can cause confusion for those of us who are trying to identify something more than half a century old by looking at just a number on a piece of cast iron. Until we can find documentation that identifies a specific builder number belonging to a specific locomotive, I can only say that it is one of these seven New Haven S1 locomotives.
I am sorry if that sounds overly critical - that is not my intent - but I found a situation a while ago where the builder's construction numbers and the railroad's locomotive numbers were scrambled within a series of 10-12 units. That was on the PRR, and among Fairbanks-Morse engines, but what can happen to one builder (or railroad) can happen to another. This is not unique to locomotives - I was told that the makers of the early Gibson guitars had serial number plates made in batches, and the assembler would pull the plates out of a box that held several hundred plates. Which one was built on Tuesday and which one on Thursday? Nobody could tell. And they still can't - they are lucky to pin down the right year.
At least, we have identified the series of locomotives we are looking for, and for that, I am grateful. From 75,000+ down to 7 -- that is a significant reduction!
Fredrail