http://reverb.com/?query=octave+pedal&utm_source=gearmandude Reverb is THE buying and selling source for all things new/used/vintage guitar and bass gear related...there's also drum and keyboard and other stuff! A large percentage of listings are in the 'make an offer' form, so you can really score some great deals. Much lower seller fees than eBay, and it's focused on music gear exclusively, so you don't have to wade through vintage Ford Mustang fenders and headlights, when you're really looking for a '69 reissue Mustang guitar. The selling format and layout is WAY faster and simpler than ebay as well. Check it out!
True story...singer dude lost my POG, and I replaced it with the Micro instead, as I was only using a subtle octave tone on it recently anyway...but this, in my opinion, is the best overall octave pedal of them all. Best tracking, and if you pull the octave levels back, it's the most natural sounding. THE BEST! Yep
I used a http://www.suhrguitars.com SUHR Pro Series Stratocaster with Landau pickups, and the http://www.drzamps.com Dr Z M12 amplifier.