I need to find a little box..

ArcticFox

I need to send something small to my friend (a small toy we accidentally took home with us) and I wanted to send her a little container of eczema lotion for her son that works wonders for my DD.

Because of the lotion, I don't want the package to get smushed even in a bubble envelope.  But I can't find a small box.. any suggestions?  Does the post office have tiny boxes?  Their tiny priority mail box is too flat to fit the stuff in, plus I don't want to pay for priority mail.

Sorry - so random - but I have scoured my house and brain for ideas..