MP4 files for Nude Yoga & Tai Chi DVD (1999) from Ambassador Video.  They are encoded in the original 720x480, but I think to create the DVD they just used VHS copies of the separate 1995 and 1996 videos.  It contains:

Nude Yoga Workout (56 min.)

Nude Tai Chi (32 min.)

Nude Stretching - PREVIEW (6.5 min)


So it is pretty much like this on Amazon.com (which says it is from 1999 too but says on the cover that it includes stretching):
 
http://www.amazon.com/Nude-Yoga-Tai-Chi-Stretching/dp/B00003UC8V