1. look for some cowhorn or moustache bars in 23.8 road diameter.
2. maybe could find some aerobar attachments you could cut down.
3. or....consider down tube shifters or stem shifters.
4. velo orange crazy bar has 22.2 ends with 23.8 horns.
5. microshift bar-ends fit "Clamp Band19.0 - 22.0mm"
(dunno if that means will fit 22.2 bars...)
the T09 version has offers friction/index on the rear.
BS-A09 / BS-T09 ? microSHIFT ? Cycling Transmission Manufacturer