You could take a picture of yours, and a picture (I guess from a Zildjian website) of the unmarked Ping ride and save them together. You can always show a buyer the two pics for comparison. I've bought/sold tens of cymbals used (most of mine are) and in my experience most people looking at pro line cymbals 'know' what they are looking at, or for, so they will 'know' a Ping ride when they see/hear it.
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