I'm by no means an expert but do keep beardies. The vivarium size sounds adequate. Obviously the larger space you can provide, the more interesting and stimulating it can be made for the beardies. If your planning on keeping 2 together it really needs to be 2 females and even then there are no guarantees they will get on. Males together will fight and if a male and female are kept together permenantly the female will get stressed from all his advances and possibly over breed.
Someone from Chester imports and breeds Fire and Ice dragons. I'm not sure if he posts on here but he posts under the user name 'woodrott' on RFUK.
As far as I know beardies aren't bred in labs for the pet trade over here. Most are bred by hobbyists.
I've never used repti carpet but I believe quite a few people do. My own are kept on lino.
Hope that helps.
