Ooops. Can you push it back through using jaws of a vise and a stack of back-up washers to clear the pin on the narrow side? Maybe a thin film of J-B Weld to secure the pin in place? Will a replacement shaft be any better?
(Edit: Is the shaft bent causing a vibration that moved the pin? Or...
@ post #46. Yeah, been through some of those searching for the part episodes. They can be maddening. Most recently had me going back to my online purchase record to verify I had actually bought the part. O.k., bought it. Now to find it. Later, found it after having given up looking for it...