Well, I pulled the driver that was giving me trouble out and it was a 6511 and it was stamped with SDA1C. It had never been removed before, judging by the effort it took to unscrew it, so it is an assumption, but a relatively safe one. I called the guy back and he does have a spare one, just trying to hook up with him as I was out hunting when he called this weekend.
If not, I hooked up with one of the "pray" this AM. $25 plus shipping. Maybe too much, but hell, I'll have an extra one. You never know.
Any yes, I am freaking impressed with these bad boys!
I can just turn up my receiver and it keeps getting better. I have had the tweeter cut out once on me, but as stated in the owners manual I downloaded, it came right back after turning things down. Realistically, in my room, I hardly think that I will have that problem. (My wife and daughter were out of the house, so I was home alone w/my son, and cranked the shit out of it!). Again, awesome speakers.