When I reformed the 1967? capacitors in MARCH's straight 8 I took some
data showing the improvement in leakage and also measured capacitance and
ESR. I couldn't find original spec for the capacitor but the values
seemed reasonable compared to datasheet for more recent capacitors.
Graphs here.
http://www.pdp8online.com/shows/vcfe15/slides/PDP-8_Restoration.html