Almost any sign shop should be able to restore those for you with the right paint
that will last anther 40 years.
Were it me, and the condition was real bad; I would take a hi res digital pic of it, go to a sign shop that does digital to plastic imaging, and have them create new stick-on decals of the right color and size. Should be easy-peasy with photoshop and the printer/materials they use for car and bus wraps.
This is easy for me to say because: a) I don't have a Compact Jr. and, b) on my Compact-II the original logo was a decal.