It will very hard to find a buyer at that price considering the current market sentiment and the item is already used for mining already plus the shipping cost. But the price is very fair since the brand new card is worth 700$ so the buyer will save 600$ if he purchase that 3 cards. But I doubt someone will invest right now in mining because aside from the value of rig is depreciating, The value of token that user mines is depreciating so its more economical to buy the token instead of mining it right now.