I know that there are things which are very close, like the 12-21, but does anyone make something with a 1 tooth increment each time? sth like a 11-19 or a 13-21 that still shifts as all the other official stuff out there? on my next setup i'm going for a tripple and a straight block. I am a climber, but there are a lot of flats where i live, and not having the right gear irritates me. Any ideas?