I think you can still get them on Amazon (I checked and not on Kindle) - the Fawcett edition I picked up was from 1955, possibly a first edition. I love these short and punchy kinda formulaic stories - probably for the same reason that I like short films - everything encapsulated in 15 minutes - which takes a lot of talent.
I got a good deal because Amazon is selling a used copy for $2.95 and paid 49 cents. I'll let you know what I think and pretty certain that I'll go back and get the rest - a full set might actually be pretty cool to have on the shelf.
Like Ian Fleming, Aarons was in the Navy. Casino Royale - Fleming's first Bond story appeared in 1953 - I wonder to what extent they read each other's stories and to what degree they influenced each other's writing.
The Sam Durell's were beside a copy of The Romance of Tristan & Iseult retold by Joseph Bedier and translated by Hilaire Belloc - got that for a dollar.