Adam magazine was a forerunner to Playboy and had a mail order LP service that sent out comedy albums, released on the Fax record label, with pretty crappy comedy or song on the disc and a raunchy, for the day, nude cover.
Adam fed off the Hollywood merry-go-round (gossip, sex and money) and the West Coast comedy label Laff also tapped the industry and it's clientèle. Richard Pryor had a live album released by Laff early in his career. Their covers were sexy/outlandish/offensive depending on your taste and typically featured b-list comedians on vinyl. Rassodock has an impressive Laff discography at:http://www.rassoodock.com/data-pages/laff_records.html#top.
There's not much info about these labels out there. The owner of one of the labels died in suspicious circumstances, so there was definitely (and unsurprisingly considering the circles the labels would have worked within) a dark side to this whole Hollywood based comedy/erotic scene. The darker side gets worse as it heads into humiliation territory. While the tragic story of Betty Page sums up much of the horror that women can sadly face in life.
In New York Joe Davis set up his Davis Records label to sell comedy LPs with nude covers and was prosecuted for his troubles.
Bolo, Que and Beacon were smaller offshoots of Laff, Fax and Davis.
African-American comedy tended to be more x-rated and albums featuring comedians like Redd Foxx and Rudy Ray Moore followed suit, content and cover alike.
Hi-Infidelity spoofed the easy-going lounge scene of the era and by the end of the decade nudity was far more acceptable. The nude cover had begun it's journey to the mainstream.