On the LeCroy 94xx scopes, the shaft is part of the rotary encoder (made by Bournes) and neither part is available from leCroy. I haven't found the exact Bournes part anywhere but a similar model should work or you can probably take a new encoder apart and get the shaft. Or just get the right encoder from salvage. For knobs, I use knobs from some of the OLD Tektronix scopes. They're red but who cares.