That was one of the very first, if not the very first, Sierra game written by Roberta Williams. I would be thrilled to have that game for my Apple ][+, but no way would I pay $385 for it. If I ever saw it in the wild, however, I would be thoroughly excited.
Chris
EDIT: OK I just looked it up, and Mystery House was in fact the first game that Roberta Williams created, and it was that game that cause Ken Williams to found Sierra. That copy is certainly not a first-run copy, though.