Dan
We've had some discussion about sway bars on the owners forum. One car (HM1010) has just been fitted a VPM sway bar to the front suspension. I believe it's the same bar that fits an FFR roadster. Seems to fit well.
Also, Dean (dlampe) installed sway bars on HM1002 but I can't remember which bars he used. They were splined sway bars as I remember.
None of us have gotten to the rear yet as far as I know, but we have looked at a couple different manfacturers.
Here's a link to VPM:
http://www.vintageperformancemotorcars.com/home.htm
Larry