It is also so close as makes no difference to the Floquil "UP Armor Yellow" that was used for the "deepest" layer on the shoulders and knees. So since I'm using stainless steel for my custom Mando (but Protector-inspired), I used zinc chromate aviation primer for the base coat on the yellow pieces (doing my green pieces inspired more by Boba's helmet, with gray metal primer under the green).
Here's UP Armor Yellow next to Zinc Chromate:
And here's what my shoulders looked like primed with it:
...And the same shoulder painted up the rest of the way and weathered:
As for an undamaged set of Boba armor, the earliest image we have of him in full armor from anything resembling a canon source (following the Clone Wars) is two depictions of the same thing -- the holo of him and Sintas and baby Ailyn when he was in his late teens and trying to live a normal life on Concord Dawn as a Journeyman Protector:
(from Outbid But Never Outgunned)
(from Blood Ties: Boba Fett is Dead)
Already has the crater in the helmet (headcanon notion: he was given it from one of the 209 Protectors that died during the Clone Wars -- from a head shot that broke his neck), already a bit scuffed.
--Jonah