Hey,
We used
www.uniqueonline.com for our rush shirts last spring and they are very flexible we had them in a week and a half and that was without express delivery. They may take longer because they have to be stitched but it’s worth a try their number is on their sight. They are based out of the University of Delaware if you feel like a road trip to go get them. If you can’t get embroidered letters what about screen printing them on a shirt. ZBT did that last year; it may not look at nice but if you need them that soon it may be all you can do unless your sisters can sow. Good luck, oh and what colony are you? I have a few friends at Duquesne.