A10, the composer credit should by rights be written as Mason, MacAulay (upper-case A after the Mac) and B10, Marvin Gaye/Tammi Terrell is shown on the label, with the slash.
The Blue label could well have been a one-off, but I've seen several Columbia budget releases carrying the dark green colour with silver print. Again, it depended on the nature of the album and its contents, to some degree, that determined the label colour. The label design, devised by EMI in Britain, was a unifying tool to bring together the Columbia, HMV, Parlophone and Stateside labels, in much the same way the singles and EP design, with the iconic "45rpm" unified these labels, along with the Tamla-Motown label, but Tamla-Motown was not included in the unifying LP label design.
Well, I found out about California Soul and learned that an Aussie issue DOES exist TMO-9128. The only question is, same coupling? The A-side was Onion Son (with Valerie Simpson replacing a desperately-ill Tammi on vocals). Understandable because Onion Song was recorded close to the time of the single's issue while California Soul was recorded in 1967 and kept "on ice" until it was put on as the flip-side to Onion Song.
Quite a few Aussie tracks here! A2, A7, B2, B3, B5, B6, B7. Seven out of the twenty are by Aussies, not a bad average! A couple of these have not seen the light of day in Australia as singles in their own right(Al Martino, Marvin Gaye/Tammi Terrell), and the Doug Parkinson In Focus track is, in fact, a B-side. The tracks are generally 1969 and 1970 vintage recordings though Neil Diamon is the odd one out, his track goes back to 1968. This is the album that kicked off the Explosive Hits series!