Keep you eyes peeled on ebay and you'll find some pretty quick. Used ones can be had pretty cheap, but you never know what kind of shape they're in. New or Like-New will go for around $20-30/stick these days.
Make sure you're getting genuine Wico- if the switches attach with screws to little metal L-brackets, you're looking at the crappy Chinese knock-offs. You don't want those. Real Wicos have snap-in switches.