Have y'all tried getting a wheel built? That way you can choose the components you want such as a single speed hub and a 650b rim and get it built up. Single speed 650b in a road bike width is not really something that someone wants these days. There is no point in QBP or Wheelmaster or other distributors of wheels to make something like that because nobody sees it and nobody asks for it. Plus you are always better of going handbuilt that way you get to get what you want, how you want it and it will last and last. A professionally built set of wheels likely won't need much truing if any and with quality parts you aren't likely to have to do much aside from maybe switch or grease bearings on occasion.