not sure where you will find your stoma bags but as suggested the hospitals are your best bet. as far as clinical waste goes it appears that any old bin will do as the recycle bins outside our house were once full of clinical slides - complete with human blood!!!!!!!!!!!!!!!!!
obviously this is not the answer and hopefully a one off...................
you will more than likely have to pay for your bags and will also need private medical insurance, shop around though as some are quite exorbitant!!!!!!!!!!!!!!!!!