The boxes can be found on UKpet supplies website -
Small Animals at UKPetSupplies.com
You'll have to search the site.
The fluffy bedding is not good for them, it gets wrapped round limbs and body or ingested and could kill them
I use a mixture of paper bedding from P@H and tesco value toilet roll, leave it on the cage floor and he drags it off into his bed, which is just an empty box that had the cat food in it. It's been cut so I can lift the lid to get him out if need be (he's lazy!)
Experiment and see what he prefers!