I swear I have looked everywhere for hours, NO ONE that I can find has the MT Street R's in a 315/50R17 size. And it's not just that size, it seems most of their tires sizes are out of stock. The same goes for M&H... I don't understand what the problem is, tires are made every single day by other manufacturers and they are not having the problems our racing tire companies are having. I ordered a set from Summit more about 3 weeks ago. They first said they anticipated having them by the 28th of last month which was fine, then that comes and goes and they change it to the 10th of May which was a little upsetting. Now a few days later we haven't even gotten to the 10th of May and they have moved them back yet another week!.... Does anyone have any answers as to why this is happening OR better yet, know somewhere where I can buy a pair of these? At this point I would pay more than normal price as I am missing out on nice weekends that could be at the track.