Oh, I'm very familiar with Beta pants - I have half a dozen of the regular (not high) waist, 3 or 4 low-cut, and some that I had specially made, cut just an inch lower than the regular-waist size. Back in AC Medical days I discovered that they had the beta pants pre-made without elastics and with just the side seams finished, and that they cut them and added the elastics as the panties were ordered, so it turned out to be easy to get them custom-cut.