Thanks guys.
Opaqueice, I am embarrassed. I thought I did my homework but I used Yahoo search, not Google. Yahoo found me next to nothing. It may have been my fault. Maybe I did not enter the proper search parameters.
Other suggestions appreciated including a good source for quality splitters. If I need a permanent pair I will first contact the maker of my current XLRs and see what they can do for me.
For experimenting my preference would be splitters that could connect two inputs 10.5" c/c. The short Ys I have found so far would need to be placed at the preamp and two pairs of expensive interconnects used. Y's with longer leads after the split could be placed at the amps and only one pair (which I already own) of expensive interconnects would be needed.