Vintage Silver Beltbuckle CMS or MCS

[Lukas]

I have a little vintage silver beltbuckle with a gold Initial on it.Somebody told me it could be made in Mexico. On the back it says Sterling and underneath is the letter "C" with the letter "M" on top and an "S" in the middle ( it almost looks like a Brand).Underneath that is 10 K which I think is meant for the gold Initial.Would like to get some more information about it.
Thanks Lukas