Value on cracked rope edge Eames Fiberglass Armchair  

It looks pretty far gone to me. Ask Eameshead......

Yeah, hardly seems worth the trouble, considering the all around visibility of the damage. If you're going to buy one with issues, you can find one that looks much nicer than this. The big missing corner chunk is a tough repair.
I don't know what you are planning to pay, but just for example, there is a dark grey rope chair on ebay (rarer and more desirable color) with a perfect rope edge and just one small drilled hole that would be much easier to repair. The corner repair will always show, even if it is done well.
Just my two cents of course. And for the record, it's been a while since I saw it, so double check my facts as I may have missed recalling something.

I can't find other rope edge that's for sale with a hole in it in eBay.....
I've recieved two repair quotes, they are between €280,- and €380,-.
The seller is looking for €500,-. Is that reasonable, considering the fact that is indeed a rope edge but damaged?

Type in "Eames Rope chair" and set to "best match"… 5th item down.
I have seen Parchment rope shells in decent shape sell on ebay for around 600 (US dollars) recently. Either way, I would hold out for an undamaged chair.

So you're looking at close to $1,000 for a chair in that condition. I personally think it's WAY too much money for a irreversibly damaged chair like that. Is there a particular reason why you're so attracted to this piece? Otherwise, I'd wait. Just my opinion.

In my opinion, it will always be a cracked shell chair (repaired or not) so it will never be worth very much. I would pass...