Your supports look working well. The cost is reasonable.
I handled ends of the handlebar as followed.
Prepared items.
Two short pipes: 38mm outer diameter, 2mm thickness, 17mm long, SUS304 Glossy finish. Got from a web shop.
Adhesive rubber sheets: 1mm thickness, proper length. (300mm long ones in my case)
Sized the rubber sheet 15mm wide with a knife.
Put stock bar end caps on the handlebar. Rolled the rubber sheets on the handlebar up to diameter around 34mm. Cut unnecessary sheets.
Once took out the end caps, put short pipes.
Put back end caps.