Well I am going to have a go at Digikey, but since they say everything is to be backordered I don't like my chances. Perhaps a group buy of greater numbers might influence them.

I am expecting them to come back to me and say "sorry that part isn't available"

For only a set of two you could buy them yourself. The only extras you would have to buy is to buy 10 power terminals instead of 4 (61c each) and 50 signal terminals instead of 44 (38c each) to satisfy their MOQ. Would work out to US$31.69 + shipping for two sets. You'd have some spares too then...

Personally I am trying for 3 sets right now.