Hi Tessa,
There are several forum members who sell the cage liners here on the forum, but they are in the states. If you look up at the top of home page you will see a list of sponsors, many of them have store items such as fleece houses, cage liners and toys for sale. I'm not sure about the wheels though.
I have ordered fleece items from Alli713 of camphor chins and also threewingedfury-Tiffany and have been really super happy with all the items I've received. Try visiting Alli's site at camphorchins.com or private message Tiffany-threewingedfury for some assisstance