With my world renowned bad luck never bought boxes, but I was told they can give mundane pet stuff too (pet tags etc)?
Yes, as far as I know pandas/puppies/kittens (pets) and pet tag. Their TT is unnoticable though.
You should be aware though, if you get a pet (tamed yourself, from a strongbox or from Another player), the big cost will be providing nutribars for it. With markup, some 10-20 PED cost maybe to get started?