Have you tried just contacting them by email first and sending a photo of the damaged piece above? I would have thought any reputable company that would be good enough and they would send a replacement free of charge without you having to send damaged piece back.
Small workmanship defect: how serious?

Actually I should contact them and see if it’s possible to just straight-up buy a replacement piece. It would likely be no more expensive if they don’t charge the cost of a whole set.

@Paleobotanical, Send a high resolution photo of the defect to HOS. I did not have to send my defective piece back to HOS when one of my Drueke repro had tool marks like yours. They just shipped me a replacement free of charge.
Everyone kept responding about HOS and piece replacement, but no one answered the more relevant question that Paleobotanical had.
“Does anyone have any experience with this type of damage and is it likely to be a problem in a few years? Or, will it be just fine if the pieces are stored carefully?”
I’d also be interested in having this answered. Can anyone help. Please, just answer the question and don’t start focusing on repairs, etc. You can do that afterwards, if you want. Thanks.🙏
Forget about replacements. Look, if you buy a set from eBay, on the secondary market, there will be no future guarantees, warranties, or anything else. Now, some of us would like to know, If a chess piece gets a hairline crack, will it continue to deteriorate or will the hairline crack be the final phase of the deterioration. Can I just ignore the hairline damage, or will the piece gradually deteriorate, even if it is properly cared for?
I purchased a wood chess set from House of Staunton in December. The white king appears to have a very small, shallow crack in the base. They have a one-year warranty that requires sending in the damaged piece.
Since I’m in Iceland, it’s costly and time-consuming to send the piece back to them in Alabama. If the issue is purely cosmetic, then I’ll just keep using the set, since I bought it for my family to use to play, not to show off. However, if this type of crack is likely to get a lot worse over time, then that changes things.
Does anyone have any experience with this type of damage and is it likely to be a problem in a few years? Or, will it be just fine if the pieces are stored carefully?