I have been searching for this song recently. It is called "No Work Today" by a roots reggae musician, Ras Karbi. It wasn't easy but I found this info in an interview with him posted online at the following link:
Unfortunately I have not been able to find the song itself. The reason is in that interview; Ras recorded some music that was never put to vinyl. But the tapes made it to some radio stations. This one was a big hit in Boston because of WBCN.
The only hope of getting a copy may be to either find someone who recorded it off the radio, or to contact someone from WBCN who has access to it.