It's just a hair under 19mm, so I would say 18mm is right. I don't know if I want a Nato - I would only get a leather Nato if I went that route. I would love an alligator strap of some sort (or just a nice calf strap). But I can't seem to locate anything I like. redface.gif
Awesome. A true heirloom then! Very cool.
Well, unfortunately, this guy isn't in the US either, but you might try a seller named "Massimiliano" over on the Vintage Rolex Forum.
He's got some nice leather and suede straps, all kinds of colors, and he can customize...I will cut and paste a little blurb here:
"There are two versions: the classic NATO and a version that I call for simplicity MODEL 1 since it has only one passage, under the watch, and makes the whole strap/watch more subtle, fresh and comfortable on the wrist.
They are all:
-made in Italy (specifically in Rome)
-by an Italian craftsman
-with made in Italy leather/suede
-with made in Italy inox buckles
For this specific reason inside every single strap you will find an small Italian flag."
Did I mention he's Italian? It's kind of funny reading all of that again..... but if you check one of his listings, his work looks pretty sharp, and even if you don't pursue it, there's some good vintage Rollie pr0n to check out there.