OK, cheap solution. Buy some matching gal steel gutter downpipe, same diameter, and some light gal steel sheet.
Chop out bits of the PVC piping and replace with gal steel. Make/seal the joints by wrapping bits of sheet gal around and securing with hose clamps. That means you can keep any PVC bends, which would be convenient. EARTH all metal bits.
Won't cost a lot.

Cheers
Roger