1. where does the seller live, the farther he lives, the more the shipping cost it will be, wich you will have to pay since he will say you pay for returns...and he has the right to do so.
2. can you live with that mark on 1 of the faces?
3. if that 1 mark is the only fault on the figure, you have to decide for yourself if its worth all of the (shipping)cost and the wait to contact the seller for a refund or a replacement. Like yellowjoshua said: is it worth the hassle of going thru ebay?
Whatever you do, it cant hurt if you just ask the seller what he can do about it!
You can for instance ask for a replacement face part?
Ask a small refund?
Ask for a discount or something for when you buy with him next time?
....seek out what is possible with your seller.
But again you gotta ask yourself, is it worth it all? Is it the face you would use on the figure?
With this figure I believe that a seller cannot see ALL the issues it has, since it is a figure with many parts + many hidden parts = under a plastic + many people dont want packages that were already opened.
So either the customer want a perfect figure but they the seller should be able to investigate a figure in detail, either a customer wants an unopend package but than customers should be aware that a seller cannot check if the figure is 100% mint.
Of course, if the issue is visible at first sight...you got a ground against the seller. But still, if that is the only issue, it would be hard and you got to ask yourself AGAIN, is it worth all the hastle?
If thats the only issue he certainly didnt do anything so wrong that you can claim a refund or a return, thats for sure.
But you can try the options I pointed out.
But I actually think the seller and/or ebay rules give the right to the customer to return the product within X-days!
So if you really cannot live with it, you can always return it withing x-days...
So I suggest you contact your seller asap and dont waist time on boards and waiting on replies otherwise you could lose some rights.
Because it would be very easy if you could return your products whever you want and demand a refund
Maybe you can post a picture of the mark on the face?