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The difficult part - can't be something a non collector would know....
If it is a brand, quite unlikely there is one mainstream brand that's under radar with so much social media going on...
Modern - maybe a Grand Seiko as many still think a GS is just a seiko; Nomos, Doxa, Habring? I am excluding the "Micros".
For me, a clean, proper vintage should work. And many are not known....