Don't want to sound too negative but the problems you will have regarding this business adventure will be at the UK end negotiating all the import business red-tap/import tax etc, not at the Thai end. If you go for it, then it's probably a good idea to go talk to some shop owners at Chachujak etc in BBK as many have factories in the north but sell in BBK.
Most people selling in Korat will be buying from these sort of places anyhow (or the Cambodian border markets), but if you are thinking of exporting then you have to send stuff to BBK anyway so might as well buy it there in the first place.
As for the pottery village in Dan Kwian , then really it's over priced and for tourists, both Thai and foreign. Better to go to BBK. Dan Kwian is OK if you want something fancy for your house but there are better places to go to and do what is being suggested here.