Keep a few Opinels, Svord, and Moras in stock so you can still sell them quality knives at a lower price point. Beyond that, look into Becker (through Kabar), and possibly a few Spyderco, ZT or Benchmade.
With that spread, you should have knives ranging from $15-$20 up to about $150. While you may not move the few higher end knives, folks will like to see them and may end up getting one as a gift around Christmas while the bulk of your sales will be from the first 3 that I mentioned.
Becker will land you as a solid user knife that should last them a lifetime. They can take more of a beating than the first three, but shouldn't cost as much as the quality folders from Spyderco, ZT, or Benchmade. These will likely be sold to those that are seeking more than what Mora has to offer, while allowing you the potential to up sell a customer that seems like he may not know what he wants, but has a few bucks to play with.
To top it off, Becker is made here in America, which will be a draw. Spyderco has some models made in Boulder, Co. and have a more inexpensive line called "Byrd" though they are made in China, the cost reflects this but they are still fairly well made. Most of the other knives I had mentioned are made outside of the U.S. .
Best of luck.