You probably want to do Titanium Nitride on a gun and not actual gold because gold is horribly soft, and TiN would probably be easier to locate a place to do it rather than gold plating, but that's just my two cents. I don't know anywhere that does TiN coatings but Metaloy may.
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Much like anonymous sex, internet based gun transactions are mildly risky, but almost always worth it.
I'm not a surgeon, why? What's a little sepsis between friends?
Everyone takes a beating sometimes