Modern Vespa

Hi everyone.
Some time ago, someone knocked over my Piaggio Vespa PX 125 (2010+ model) and caused the handlebar (at the throttle side) to be damaged. When I removed the handlebar grip I could see the (washer) attached to the (throttle tube?) was pushed inside the red housing and it looks bent. At the moment the throttle handle will not turn.

So I'm thinking I need to replace the throttle tube (assuming I can get the old one out) . Any advice / know of any guides on how to do this. I found this thread about a similar problem so hoped I could get some help here.

This is the first time I've opened up my Vespa so forgive the lack of correct terms/techie stuff.

Thanks in advance for any advice.

Get into the headset. Tubes held in by the pulleys (gear select one side, throttle the other). Need to work out where the damage is - could be the headset/switch housing itself.

https://www.scooterhelp.com/tips/body/fork.bearings.html