Please Note:
I have not personally verified, in any way, the viability of substitution info posted here. Also, suggested substitute parts may or may not be pin for pin drop in. It is suggested that whenever considering a substitute that the builder check reliable data sheets and compare the specs of the schematic's called out part number and the candidate substitute.
This page comes complete with a "Your Milage May Vary" caveat.

On This Site

...Data gathered from the people on the Synth-DIY list...

Common Operational Amplifier Comparison Table
Preferred Components Lists of Synth-DIY Members
Parts Substitution Information

  Here are some links to
public cross reference sites: