Technical Gearbox selector shaft bushing?

[dapedza]

Hello experts. I’ve stripped both the original 500 box & the 126 synchro box. Both castings show wear where the selector shaft lives. Even after I renew the o rings, I’m sure it will leak. Does anyone have experience of machining these castings and fitting a suitable bushing? Thanks!

 

[dapedza]

Think I’ve found the answer to my own question. These end casings are available from Ricambio for £56. You’d never get the machining done for that!