Mugen RNR question

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I'm looking at a set of what might be Mugen RNR's but something is a little odd. He had these things fully polished from original black/red. But when I looked at them they had absolutley NO stamps or markings on the lip at all. Now, this might lead you to believe that they are fakes, but even Rota Group N's, Lenso Fusion R's, and The Tenzo knock-offs have stamps all over the lips. I looked on the inside of each wheel and the only markings I see are the letters "JPN" on the inside of one spoke on each wheel. They have Mugen center caps, but they fit all reps so that itsn't doing to tell me anything..

I am stumped on why that these wheels have no identifying stamps on them. Surley that when they were polished they weren't removed somehow?

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