One thing you have to look out for is the size of the 7-Eleven shops you look at and what merchandise they're carrying. The stores are franchises, and the franchisees don't always carry the same merchandise. I know for a fact that some don't carry playing cards at all because the franchisees/owners don't find it worth their while to stock playing cards over some other product with a better profit margin or that sells faster (in other words, something more profitable in general). It's possible that such shops won't carry these at all. This will especially be the case in smaller locations with less overall display space and locations where real estate is very expensive to start with.
I've found one chain drug store in my county where the owner himself told me he refuses to carry playing cards at all because he felt they weren't profitable enough! No decks at all - no Bee, no Bicycle, not even a cheaply-made dollar-store deck anywhere.
If your local 7-Eleven doesn't carry playing cards at all, it's possible they won't get these and you should try another location rather than wasting time on return trips to find them.