Anything CampI is expensive. I'll have to double check but I think 39 was the smallest for the 135 BCD. CampI usually listed, but try finding, every tooth from 39 to say 56ish.
Sometimes you can find like a Strongligh or Ofmega brand to fit CampI
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk