OK, here's the correct answer.
This is a standard 34# Lucas/Delphi injector that has been modified by putting the threads in them. They were never available as a stock part. The part number is long expired, and that's why you can't find it anywhere.
The are an improved design over standard injector, in that it uses a free flowing disc instead of a pintle cap.
They can be cleaned, rebuilt, and blue printed, just like any other injector. There are lots of places around the US that can perform this service. I sent mine to The Fuel Injector Connection 2 days ago (Tuesday) by FedEx. I just spoke with Bruce - they are finished, and he is going to express ship them via USPS today. I should get them by Saturday. Total cost including express shipping is $166.
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6/29/12: Rebuilt injectors arrived today (Friday) by USPS express. That's pretty fast service.