Do we have a source on this?
There was an article about it somewhere... But at least the pickguard for sure wasn't original when it was in Kossoff's posession. As someone mentioned, mint-green pickguards firstly appeared in the 60's.
Also Dave likely repainted it to black.
Edit: From Ground Guitar (likely lifted from another article):
Even though Dave checked the serial numbers for the accuracy of the previous ownership, the guitar somehow didn’t feature a white finish anymore but was painted black.
Also, the body was allegedly dated to the early 60s. This would mean that Kossoff actually had a Parts-caster, or that someone swapped the bodies from a white to a black one at some point. Since Dave doesn’t seem to mention or explain anywhere whether he did this, or whether the guitar was already like that when he got it, we’re left to speculate.
A theory that could potentially explain why this guitar features parts from a couple of different models, is that Paul Kossoff could’ve acquired it from Eric Clapton. Eric bought a couple of Stratocasters in the early 1970s and used what he thought were the best parts of each guitar to assemble his ultimate guitar, now famously known as “Blackie”.
Since Paul was affiliated with Clapton, he could’ve ended up with a guitar that was assembled from the remaining parts, but it is commonly agreed upon that all the guitars that Clapton bought that day were mid to late-50s models. Since we know that Paul’s Strat allegedly featured a body made in the 1960s, this theory doesn’t really hold water.
Also, here is Free's My Brother Jake with the Kossoff Strat. Clearly it has a 3-ply mint pickguard. My theory is that the neck was a gift from Clapton and Kossoff simply replaced the original one (Clapton liked to rave about maple fretboards back then).
Funnily enough, the guitar in original state minus the neck looks like it's a twin of Janick's 63 (2nd from the right).
