Two on Craigslist here in Tulsa. Newer ad is for a 1986 ST-500, 23", $235:
https://www.craigslist.org/view/d/broken-arrow-st-500-cannondale-touring/9rHqv5rCXXVJ2V4XgJvKYm
Also, a 1986 SR1000, not a Black Lightning, but a Black Lightning frame with Dura-Ace components, 54cm, $400, no pictures...