Hi PhilMH,
I entered the year 1973 when I submitted this item, and that was admittedly an estimate. The May month was added by user stephenwyatt1967; I don't know anything about that...
Since my last comment, I've obtained MCA's January 1974 catalogue, where this album is still listed under its old Decca catalogue numbers, so it was probably later in 1974 that this catalogue number came into use; where does the May 1973 date come from?
MCA Coral was probably accidental, or one of the factories had run out of proper MCA labels, as I've seen other MCA reissues in the 37000 or 1600 mid-price series (e.g. The Who) where some pressings have MCA Coral labels on them; this one also exists on the three main MCA label designs - black & rainbow, brown & beige, and sky-clouds-rainbow.