Ok, the EHX MicroPog has both one up and one down which can be blended to taste with your clean signal.
The EHX POG has 2 up, 1 down and the EHX POG 2 (which is also programmable) has 2 up and 2 down.
The EHX HOG is arguably the most powerful, it has 2 octaves, -1 octave, Original note, +5th, +1 octave, +1 octave +5th, +2 octaves, +2 octaves + 3rd, +3 octaves, +4 octaves. It is also the most expensive by a long way.
Those are the Electro Harmonix offerings which seem to fit the bill, there are other manufacturers out there too but I only really know at the EHX ones to be honest.