montres1
1054
Love it !!! UG is such a great brand, and finding the correct buckle (regardless of the brand is so difficult), I agree with you, when buckles are sold, they should be bought just in case !!! :D Congrats on the collection and please share your UGs !
Here are mine (to date):
Old one from 1943:

Polerouter estimated 1960/61

And lastly the Monodatic, apparently very first series (1951/52). You can see the case design from Genta that was then used in the Polerouters :
None of your buckles would suit me !!!