[davemc]

The parts lists says 30-2171, but the part itself is labeled 30-2171-X and definitely says NON POLARIZED - maybe Philco made a change. It functions as the RF/converter screen bypass and oscillator filter cap. The main filter cap in the power supply says electrolytic.

I see no reason why it has to be non-polarized, and will restuff with standard electrolytics. Maybe they wanted a paper type cap in the application, vs. an electrolytic. I might cheat and install a .1uf film cap across the electrolytics just in case (if there's room in the can).