Just cribbing from Wiki, the generator contains 11 pounds of Pu-238 and produces ~150W of electricity from ~2000W of heat. It's hard to put an exact price on it

Just cribbing from Wiki, the generator contains 11 pounds of Pu-238 and produces ~150W of electricity from ~2000W of heat. It's hard to put an exact price on it, but it's definitely in the $millions per kg. It's theoretically feasible, but the cost would be, ah, prohibitive.