From my PC archive - no idea who originally took them so cannot give credit.
Yes you can get repos (I saw some for $230!).

I've no idea how well they work (or even how they work - I thought they were dust covers) but FWIW
- usual comment that Mopar must have had a reason to spend money on them
- they were in the bottom of the quarter on my car, never used them but will refit eventually
- with all the wind noise (and other noise) and turbulence in a classic Mopar, and particularly in a convertible, I'm sure you would not notice either any noise reduction or some streamlining effect.

If I didn't have them I wouldn't bother getting them