Sorry-I've been out of town and couldn't post for some reason on my company laptop.
I ended getting a standard 168 dual pattern and drilling out the mounting holes and adding the 2 other alignment holes. It was simple enough to do on the milling machine at our main shop. It has a nice turn table to get the holes on just the right degrees.
This is a Bow Tie Overdrives torque converter, and the mounting holes are on the smaller-(10 3/4") of the dual patterns. It's all together now and sitting in the chassis.
Thanks for all the replies.