Thanks. The damage is, in my opinion, only cosmetic. If I wanted to react to it at all, I would simply use Winn tape and recover the grip and butt knob. Or only the grip, with black.
I don't see what is in front of the seat, but to me it doesn't matter. I would not disturb the seat. That is getting into major work with little value.
To take off the grip and butt knob, first use braid fishing line between gloved hands and cut the existing EVA off, including carefully removing the winding checks. Try not to damage the area between them. You don't have to have it perfectly clean, but you need to provide surfaces to which you can solidly glue new components.
The problem is that the blank has taper, so when you load the new parts from the rear, you have to have an inside diameter that will clear the butt. It will then be sloppy on the blank near the seat.
What you need to do is 1. Get a replacement grip the same length as that which is on the rod now. (same for butt knob). Ream it to clear the butt diameter. 2. With masking tape build at least two , probably three, arbors on which to glue the new grip. Build them to be the same diameter as the ID of the grip, or slightly below to allow an easy slip fit over them. One should be at the reel seat, one at the end of the grip, and one in the middle. What you are doing is providing a cylindrical surface on which to glue the new grip. 3. Get some epoxy adhesive, (best is 10 minute paste designed for rod making, like U40 or Flex Coat) not wrap epoxy, and totally encapsulate the tape arbors, be generous with the adhesive. Slide the new grip onto the rod. If any epoxy comes out at the reel seat, carefully try to pick it off with a knife or other precision instrument. Then use 90 % alcohol on a paper towel to wipe off what might remain. Wipe, let the alcohol evaporate, then wipe again with a clean one wet with alcohol. Keep at it until there is no evidence of epoxy. Let that set.
If you want to use winding checks for appearance, it won't fit as well as the original since it has to be loaded from the rear over the larger butt diameter. But, it will look ok if you carefully center it on the blank and use epoxy adhesive to attach it to the grip.
The butt knob winding check has to be slipped onto the blank now. The butt knob should be drilled to allow an easy slip fit to the butt. The taper is not an issue now in the last couple inches of the blank. Glue the butt knob on and carefully apply a little epoxy to its end to capture the winding check. Do the same cleanup routine as you did for the grip to seat joint.
Getbitoutdoors.com will have all the parts you want. You will need to order winding checks that just clear the butt diameter of the blank.
Good luck. I'd try the tape first to see whether I liked it before going through all this.