Kral Arms Kral fill adaptor - need o'ring

Brethren of the Kral Clan, I am in need of your help locating a valve seat for my beloved Kral guns. The 2nd gen Kral Knight has an odball sized male fill valve that I cannot find a source for replacement.

I filled my bottle too fast, too many times and I have blown the valve seat gasket. It is a flat gasket that is approximately .375mm thick, 2mm id and 5mm od. Do y'all have a known part number - Kral RC26 is what I have cross referenced on exploded diagrams, or even better, a direct source for that little piece of rubber mischief?

Thanks to all -
Shoot'em good
 
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