Hi again Ken
I just received a shipment notice from Mouser for the RM15TR-C(71) caps. I was worried that they might substitute the same one that they recommended for you, but they are sending the ones that I ordered. I will find out when they arrive on Monday April 26.
FYI - These caps shipped from Mouser Canada. I don't know if they have more than one location, but it is possible that they were only out of stock at the particular location you were trying to buy them from.
I will keep you posted.