I don`t think most people worry about a tire being exactly XX mm wide, but I guess maybe you`ve got some kind of clearance issues or something. Since they`re a fairly popular tire, maybe there`s a local shop with one or both those sizes in stock? If so, after you explain what you want, they might let you mount one on your rim there in the store to see. Otherwise, I`d go with Harris, as mentioned in response to the first poster. In an apparent dyslexic episode last year, I mistakenly ordered 23mm tires rather than the 32s that I wanted from Harris (they happened to be Paselas) and didn`t notice until I had already mounted one. When I called Harris to see about exchanging the one that I hadn`t yet mounted, the guy told me I could even exchange the mounted one too! To top it off, they paid the return shipping, so I only had one extra shipping fee added to my bill rather than two. IMO, service like that is WAY above and beyond.