Related question:
How much percentage should we expect for prices here versus the mainland, to pay that "paradise tax"?
I don't mind supporting local (and in fact I always try to) unless the prices are just too ridiculous, and I factor in the transportation and convenience of getting stuff here (not just firearms, anything else).
I've been to NC 3 times in the past 6 months. Each time, I've gone to different ranges, gun shops, and sporting good retailers. Here are my observations...
We on Oahu are getting more ammo delivered than NC gun shops. I think it has to do with Hawaii LGS always needing to order way in advance to keep inventory flowing due to the distance and cost of shipping. So HI retailers' orders were placed ahead of the mainland stores when the craziness started. The mainland stores were used to getting deliveries in a few days, so they didn't have to routinely order large quantities.
We are getting better prices here for both guns and ammo than the mainland stores I visited. Again, with low inventory and peak demand, the stores all raised their prices. HI stores are getting their inventory now, but the mainland stores are still waiting their turn, particularly for .45ACP, 9MM, and .22LR.
Many of the shops also have public shooting ranges. They are having to hold back ammo for range members & other customers or risk having a bunch of empty range lanes.
I recently bought a Sig P226 MK25 9MM at OGC for $949. Bass Pro Shop in Concord, NC, and Shooter's Express in Gastonia, NC, both had the same model for over $1,100. I know they have the standard 15 round mags, and mine has the 10 rounders, but both capacity mags come from the factory that way.. That should not increase the cost for lower cap mags.
I've taken my own ammo to NC just to make sure I have some. Really, it's hit or miss there (no pun intended). Inventory is coming back, but ammo, IMHO, seems to be relatively more plentiful and cheaper in Hawaii than the places I was visiting in NC and SC.
This is purely anecdotal. Hope that helps.