It will be fine. In fact the 470n is a better choice for the output cap, it gives a cut off around 40Hz, with 100n it would be around 200Hz.
From here:
One at the input, before the 100n (or 470n) input capacitor, would work:
The value of the pot isn't critial. One in the range 10k to 100k should work. Ideally it should be an 'A' type, with a logarithmic taper. If you only have a 'B' type, that won't do any harm, but it won't give a linear control of the volume.