1) I've never found suffix makes much difference in dual opamps. I think most of the suffixes indicate packaging type or temperature rating, or some other parameter that usually won't be too important in a 9V pedal. To be honest, I usually re-sort the Pricing column at mouser by clicking the little up arrow and I nab one of the cheaper ones. If a very specific one is needed, it would be indicated in the BOM.
2) I think there are some pretty good references out there already like the faq at diysb. But if someone wanted to tackle the project I'm sure it would be appreciated. Maintaining and updating something like that as things shift and change (especially if you tried to include direct links to products) might prove to be problematic, though just a simple cross reference spreadsheet would be good.
Here's one to start off.

TL072
cheap sub NJM072
fancy sub TLE2072
^^^btw, you can do the same subs with TL071, TL062, TL082, etc.