I am running a Mavic Comete Pro Carbon SL UST Wheelset that I had for a few years (and love btw).

Running them tubeless. love the setup. All good for years now.

Recently I ran a flat while on training in FL and had a local bikeshop put on a new tire with innertube since they did not have tubeless.
Long story short I now (weeks later) noticed that they omitted the little ring that adapts the round rim profile to the flat nut on the valvestem.
Have been looking around for a spare but having a hard time finding any. I know Mavic went through some trouble and i am actually not sure whate state they are in currently.
I cannot find any Mavic dealer in the US that would have spares (all only selling new wheels).

Would anybody know where to find that little piece (pic below)?
Maybe another brand would fii (or closely fit) since Mavic apparently uses a "standard" NACA profile.

Any help is appreciated.
Here is the part I mean: