Usually - but HOW depends on how fastened down and material type. Sometimes screwed in, sometimes nailed with greenhouse screws of plastic, sometimes clamped down with a firring ro mouinting strip, sometimes engaged in slots in metal locking strips that are screwed down. You would have to look at how fastened and how to remove, then look to get replacement material (if still available).
Commercially, usually there are local companies which sell awnings and pagodas and patio covers and such who can do this work - I thing Awnings is the only Angies List category close to this, along with Builders - Garages/Sheds - but a bit of calling around should pop up a vendor or two for this, which you can cross-check by name on Angies List to see if they are rated.