No unfortunately I have never seen a company make that size basement unit available in a stock size. Mow that is not to say that is the case in the entire country but the last place I would expect to find anything other than the most popular standard sizes would be Lowes or HD. Try a local lumberyard or building supply center, they may have it, but they may have to order it as well. 17 days is not bad on a lead time for special order but I don't like buying windows from a HD or Lowes and would not recommend buying anything from there besides a basement hopper.

Try Dale Lumber, in your area somewhere.

You usually have to be a contractor to get access to the supply houses, however, they have custom made windows that can be made to fit that application and some can be available in a week.