I know sram do the huge cassette range of 11-42 but do any other companies do soething along them lines. Recently bought a 29er with 10x3. Wanted to make it 10x1. Wanted something slightly larger than the 36 on the rear. Ideally a 38. Any suggestions. I've got an XT cassette so pretty sure the top 3 sprockets are all joined do any companies make a set up so i could just replace the top 3 of the cassette?