I paid 10,000 currants for the one I bought at the auction. That was in the first week after reset, though. I had a feeling they were going to be a very limited item at the time, and hadn't gotten one from my pickle yet.
Neither of them is for sale though. Good luck locating one.
I bought mine on Auction for 8k. I got lucky, for sure, but I have seen them there regularly for about 50k. If you are watching for a GNG block, just watch the page a lot, or look for an auction sniper to help you. Good luck!