Wow, nice job and great pipe Al.
I think you are right on with the date range, but let me add some thoughts. There are a few interesting things about this pipe;
First, we know that Eire came into being in late 1937 so we can assume that as a starting point. Peterson tends to use old stampings, sometimes much later than we expect - Eire and other odd stampings possibly through 1948 from what I have seen, so that gives you a range of 1937 - 1948.
The "P" in Peterson is the old fork style, so still good on that count. Here is where it get's interesting - The "Peterson Dublin" (with no "of") and the single "K" in non-serif font to me points to an early Eire pipe.
Add to that the odd COM stamp. You would expect to see an Eire pipe COM in circle format with "made" on top, "in" in the center and "Eire" at the bottom of the circle. A very odd COM stamp indeed - can't say that I have ever seen this before. I am guessing here, but it is possible that they just did not have the circle stamps ready if this was early production - That would narrow it to late 1937 - 1938 in my mind.
The stem in this era would have had the "P" stamp, not the "K" stamp - the K stamp I believe came into use with the "A Peterson Product" pipes in the 1960's. The 1960's pipes also got the "'K'-Briar" stamp, not just the "K".
AND on top of that, a unique panel shape - very nice pipe indeed!
P.S. sorry about the brain dump, this pipe got me excited :D