I saw a video of this testing at a presentation done by Jim Payne back
in the 80's. *Supposedly you could get one from the Air Force but I
was never successful.

I too have seen the video - it was interesting in that it shows both
the pitching moment as well as the change in rotation rate associated
with the pitch oscillation. Way nose down and she really spun up -
nose high and the rate decreased. All of this was due to the accident
at USAFA with a civil passenger (family member of academy staff if I
remember correctly) on board. Some thought the CG was aft of spec,
although the numbers didn't really prove that. Enough of old and
faded memories.