I need an optical reflex sensor...

[Gnome]

..that works and donæt cost a fortune.

I've seached my local store, but all the ones that looks perfekt has a range of like 1 mm, and that's not enough when I wand to make a switchless system for my wah.

Any suggestions?

[Vsat]

How much range do you need? (I am guessing just a few inches)

Could be worth while building your own position sensor using a cheap laser-diode pointer (less than 1.00 US). Nice and bright.. simplifies circuitry.

Use an LDR or large-area  photodiode for receiver. Either make the receiver movable, or make the laser movable, or make a mirror or opaque light-shield movable, to vary the amount of laser light falling on the receiver. Would have been crazy to do this 10 years ago... but inexpensive now.
Cheers, Mike