how about putting them into something like this?
http://www.livefoods.co.uk/product_info.php?cPath=46_44&products_id=712
seems a bit small - ur best bet is wilkos a big tub as u can get space for be around a fiver and then plant mesh or something to cover top and let air in they cant climb the sides either well my black crickets can not and they seem very happy. just grab a little tub shove some holes in and soil inside wet for mating and another tiny tub for food saves it going in the bran
actually i think i might try growing Dubia Cockroaches instead might be easier to breed and look after compared to crickets