Personally, I wouldn’t try a big box store. Try a small shop and just make a curious inquiry. Perhaps use my story.
I’m not really shopping. Just curious about what’s going on out there.
I bought so many mags for my SKS before the ban I could barely carry them all fully loaded.
What bugs me is not being able to buy a new pistol that uses mags with more than 15 rds. Among other reasons I’d like a new pistol or two more capacity is a big one.