You should look at Radio Shack or any other store which carriers electronic components. The rotary switches sold in guitar stores are often expensive and intended for pup switching.

Here is a picture of a suitable switch at the website of a distributor from Germany.

IMO, the following five capacitors are a good starting point for humbucker-equipped guitars: 330p, 680p, 1.5n, 3.3n, 6.8n.

Just solder a 10M resistor parallel to each C to avoid clicking noise.
Let the thunder roll and the lightning flash, I'm doing alright for country trash.