71 400 Engine WIW

I've got a friend who found a complete 71 400 motor. He diassembled it and sent the block to the machine shop to be checked, which magged good. He's also got a steel crank from a 440 - perfect for a 451 Stroker. He is contemplating using this combo in his 78 mil spec truck but also thinking to sell it as well. I told him I'd ask the experts as to what his block and crank is worth (just in case he decided to sell).