While it is so tempting to touch-up a white bicycle with white testors (or any other available white paint), the problem is achieving an exact match. A frame painted white in 1969 is no longer white...it has morphed into a shade that has no name.
I have two PX-10's from that era...one is nearly pristine, but the previous owner used white touch-up paint to repair a few small chips, and the close-up result is...well, it looks like a fake Monet.... The other has 40 years worth of chips and paint dings, but it seems so authentic...
Pat Moffat
Tempe Arizona USA