Sadly, the brick has been sold — at a price of $14,449! More on its backstory from the product listing:
"This brick is 25.65g of 14K gold (0.8246 troy oz). The brick is the same size and shape as the original 2x4 LEGO brick.
This incedibly rare piece was given to LEGO employees that had 25 years of employment at the Hohenwestedt, Germany factory and was also given to couple of very special business partners of LEGO of the time. It was only given out from about 1979-1981, only one or 2 per year from my understanding.
This amazing brick comes in its original display box which features the LEGO logo of the time that it was given out."