These are really hard to find. Try Russell Church at 618-594-4596 (before 7:00 PM central time). He used to have some but would not sell them alone. He sold a set of weights and the screwdriver as a package. Don't know if he still has any.
You might also try
Commemorative Arms
That is Nick Riggio at Commemorative Arms Company and his phone number is 314-771-5700.
Nick has lots of parts, manuals and cases (some reproductions) and may have a screwdriver. I believe I heard that he was going to try to reproduce them, too.
- - Buckspen