I just bought 5 of the large size hide boxes from RBI last week, and as with all my orders from them I received them in a very timely manner (shipping was $6.99 as Rich stated above which I think is completely fair).

Only thing with the large hides (13.25" wide) is they don't fit completely flush sideways in a 41qt sterilite tub. This is easily remedied by shaving off a bit of plastic on the lip of each side, I used a band saw but any small saw or dremel will do. However, they do fit sideways perfectly in a 28qt sterilite tub.