I thought about 3D printing new knobs. But then I decided an even better idea would be to 3D print some adapters. A regular Boss style MF-A01 could go on one end with the other end sticking out behind the skirt, a near clone of the original. After some trial and error I got something that fit on the SX-150 pots and had the right length.
I liked it enough to replace all five knobs, not just the two missing ones.
Did I mention there was some trial and error?
