Looking over his Ebay listings he does have EVO parts for sale. I did not see the part you need but if I was you I would email him and see if he might have a old broken gimble that he could strip out the part for you. Worth a try I would say.
Autel will not just sell you any parts unless you send it in for repair. Might be another option. Sometimes they cover shipping both ways even if its not under warranty.
This is something should be serious for the autel drones. Most Drone repairs shops refused to repair the drone ; not because they don't know just because they cannot order the parts. It also keeps many new buyers and repeat buyers who upgrade their toys , you wouldn't invest $2000 into a toy you cannot repair at local repair shop or cannot find parts for repair. Most of the teck repair shops do not recomment buy evo for the same reason. I know international shipping is expensive and many times damages the products as well.