Jim, there are whites.. and then there are whites. I purchased a baggage door in "original" white and it's almost like a
light beige. Definitely not a bright white, but certainly not yellow either.
You have a couple of options. Is there any piece that you can take off and take to a
paint store to color match? OR, how about putting a decal over the repair....
Hopefully someone with the same vintage
Bigfoot will pop in with the actual answer you seek.