Where can I buy MRE's, meals ready to eat?

I’m not talking about dinners in a box, where all you need to do is just mix everything together but more military survival food kits? My late husband worked at a naval base as a civilian and he sometimes brought homes these MRE’s. I thought they tasted decent, they weren’t bad.

I’d like to know where to get these in physical locations to pack in my emergency bag.

I know you can buy them online, but are there any physical stores that carry these?