Hi,
A primary mirror in a common reflector cannot be polished as such, only carefully cleaned, and that as little as possible. There should not be swirl marks from a competent cleaning.
If we define polishing as removal of small amounts of material, all that happens before the mirror is finally coated with reflective material, in a very thin and vulnerable layer.
So once the reflective coating is so damaged (not just dirty), as to degrade performance, the only practical option is re-coating, as far as the mirror is concerned.
In fact a few light scratches will not make a huge amount of difference to the scope's performance, but I think that is not the point.
In theory if you buy a new scope, you are entitled to receive all parts of it in as new condition, both visually and optically. In your position I would not listen to any arguments that a visually flawed mirror will still give good results optically.
Strictly legally I think that you are entitled to return the whole scope to them at their expense (although that last bit might get difficult) and require a replacement scope or a refund. I believe that it is at your option as to whether it gets repaired in some way, and personally I would refuse that option. Also I would not disassemble the OTA and mirror cell whilst it is under warranty, even if they ask you to.
Now the confusion begins. I don't know what conditions and limitations they place on shipping damage, or if such can be made to stick (if they say that).
If they will not respond in a favourable way to several polite requests (keep a record of everything, when and where), you might need to contact the NSW Dept of Fair Trading.
BTW, if the vendor is who I believe you mean
, they have a reasonably good reputation to protect, and I'd be surprised if they did not try to clear up any trouble.
Cheers