Swing Lee O'Neill plays tenor on a Verro date by Billy Butler recorded in Chicago.
Swing Lee is also the title of a tune on the Yusef Lareef/Von Freeman cd.
He probably shows up as Swingley O'Neal in the John Young chapter of Dempsey Travis' An Autobiography of Black Jazz.
Not unusual for pressing plants to have over runs, shelve them and (if they are nice) eventually offer them to the label. Otherwise they are scrapped. I'd guess this means Mosaic has some partial sets too.
Evan Parker's Monoceros is a wonderful recording - originally a "direct to disc".
Also a solo date by Gunter Christmann (trombone and bass) on Ring/Moers. Don't think it made it to cd.