If you're good with a tig welder or know someone who is I reckon you could salvage that shaft - weld some onto it then use fabric emery paper or a dremel with someone turning the clutch by hand whilst you work the shaft to get the correct diameter and recut the threads - biggest difficulty I can see would be getting the tap to start - if it doesn't work you could still tig weld the sprocket & not onto the shaft
Check out post #218 here, i used a laser level to check the sprocket alignment front to rear https://2fiftycc.com/index.php?threads/my-90-fzr250-3ln3.8776/page-11
just an update, so I bought another fzr250, which ironically has the wrong front sprocket on it as well (Except the nut isn’t welded) so I’m going to replace it with the correct litetek front sprocket I bought for the other fzr250. -Can anyone help me out with a torque setting for the front sprocket nut?? *note f’n tight is not a torque setting lol
I know it is in the manual supplement because I have quoted it before. There is one in the resources section and one on my web pages. 3LN1 but same thread.
In English ... https://www.2fiftycc.com/index.php?resources/yamaha-fzx250-zeal-tightening-torque.127/