My wife does counted cross stich. She's really good at it. We've looked at selling some of her items, but like someone else said, the people that would buy the items won't pay enough to make it worth her time. For instance, she did a large last supper piece. It took literally a year to complete. It's gorgeous, but if we were to sell that, we'd have to charge at least $10k. And that comes to about $4.80 an hour. Hardly enough to make it worth her time. We are still looking at the possibility of selling some of her smaller pieces, though.
From my observations, the people that know how much time and effort goes into this are the same ones that can do this great work themselves and typically don't buy this sort of thing. The ones that do buy the crafts and have the money for it, have never really done the crafts so don't know how much time goes into doing them, so don't want to pay what it's worth. Kind of a nasty circle.
However, if you have something that doesn't really take that long to complete and is fairly unique, you should be able to pull it off. The key ring thing sounds like it's new enough to still be interesting, and it's custom for each person. To me it sounds like that could be a decent opportunity.
F_M