i think you may be hard pressed to find something that narrow.
apex mfg bars seem to have a nice, narrow mounting bracket, but even that is about 1.75"...
i have woodcrafts with a 2.5" rise under my triple, works like a charm.
I actually just ordered a set from apex. The person I talked to said the clamp height is 1.25" for the standard clip ons, 1.125" for the risers. I thought I saw a pic of someone's monster here that had the clip ons mounted above the triple.