Being 40 myself, a birth year watch would mean more to me. Not to mention the thought you put into the gift.
You can find a day date model Seamaster from 1972. It will have a 7xx series movement, one of the last of the legendary Omega movements. (the movement is the engine inside the watch)
Anyway, best of luck to you.
The chances of finding a 752 Seamaster from that year are slim to none, unless you are talking about one of the cushion-type cased examples. Most of those contain the 751 (a plus), but I don't think that style is particularly popular. I think there may have been a Geneve that ran with a 752 into the '70s, but I could be (and likely am) wrong.
I received my SMP for my 40th. Although it is a quartz, it will still be passed along. I bought a Seamaster (used) for my son when he gets old enough which was made in his birth year. For my birth year I went ahead, did my research and made my own purchase. I enjoyed the whole process and it wasn't overly indulgent at the same time, so win-win.
My vote for a brand new heirloom to pass down to generations still stands. :thumbup: