Labelling over hotstamps can be tricky. If you use a label that is thin enough to fit in the available recess depth, it's likely too thin to completely hide the hotstamp ridges and lumps. Conversely, if you use a label thick enough to hide the hotstamp completely, it's probably too thick for the inlay depth (and it may have adhesion problems since it'll only stick to the high spots, the ridges and lumps themselves.)
That said, for used chips, labelling over hotstamps without milling or scraping can work, if you don't mind a little bit of lumpiness that you can feel, or sometimes see in the right light.
To be clear: These are unlaminated labels, 0.10 USD each. I also offer hotstamp removal (milling) which is 1.00 USD per chip for circular inlays, 1.50 USD per chip for shaped inlays. This includes laminated labels (0.15 USD each, two per chip) and the work of applying them to the chips.