If you choose repair over replace try fixing the damage with j b weld waterweld epoxy putty.
How to fix a oval glass plastic door molding.
Use a nailset and a hammer.
How to replace the oval glass in an entry door.
Once dry it may also be painted.
Insert the tip of a putty knife under the molding.
Tap down any loose or exposed brads holding the wood molding to the door around the glass.
How to replace the oval glass in an entry door.
Do all four sides.
Should you need to stain the repair or the entire fiberglass door consider minwax gel stain.
It is rated for application onto fiberglass and other plastic surfaces.
When the molding lifts up 1 4 inch move the screwdriver to the next side.