bordering on unfair enrichment

Mr Price Mobile contacted me with a deal on a Prestigio Multipad, which I agreed to. after receiving this item and having removed only the cellophane wrappe, I realised this is not what I am looking for, I am now being charged a return fee of R768.63 for a product which could easily be re-wrapped and resold. The SIM card has not even been opened, neither has it been activated. I am willing to pay a R200 return fee but close to R800 I find unwarranted and ridiculous to say the least, it almost borders on unfair enrichment. What does an honest person do to avoid being taken for money they can ill afford.