How much were they the last time you were there? I don't recall the exact price, but I am pretty sure they are over the $4 mark this year - unless there is a tiny size I don't know about. It won't hurt to ask. They are cute little tins!!
In terms of being a single serving, I doubt this will count though. I think that falls into the "box of donuts" category where a tin of mints may not be considered a "snack for one person". Still, you never know. Bizarre things have happened!