[morzh]

Robin

If you go here:

http://www.nostalgiaair.org/PagesByModel...013793.pdf
(the link Sam gave you)
And look at the sch, part 49 ( 3793-W, which is your part) you will see it is 0.015uF capacitor.
For substitute use any adequate line voltage (250AC) Y-rated safety cap.

Same sch has other parts like 3903-AP which is #30, 0.01uF. The voltage at the position 30 can be 100V, quite enough.
Etc.