Thanks LabMonkey!
I found some hot-stamped solids and just applied the labels overtop, no milling out. I have looked for a company to professionally mill them, but have had trouble finding one, plus I'm not totally sure I want to deface TRKs. So for now, I applied labels to one side of a barrel to see how they stack.
For me, the upside is having quarters ready to go, not defacing TRKs, and they stack well with one label. Not sure about shuffling, but I imagine most would want to shuffle the higher denominations from this set.