Here are a couple of more
free downloads from Books in Motion; I didn't see these listed in the OP. I have to wonder how good they are, given that neither one of them are sold at Audible. Anyway, find out all about them by following the links below:
Treasure of Sorat. By Anthony G. Wedgeworth, narrated by Jerry Sciarrio.
The Team from Hell. By Loren Robinson, narrated by Rusty Nelson. Don't let the four-letter word in the title scare you, the audio is rated "G."