[sdiy] Looking for 45mm Alps slider with center detent

[Oakley Sound]

 > It is marked "10KW".  Not sure what the W stands for, but it appears 
to be linear from measuring the other ones.

Its not exactly linear, but it is quite close. See here for more details:

http://www3.alps.com/WebObjects/catalog.woa/E/PDF/Potentiometer/RV_RESISTANCE.PDF

Roland spares would be your best bet for parts like this.

Tony

www.oakleysound.com