The three shows in this post were all favorites of mine as a kid. The books were all tie-ins, though I don’t believe that phrase was in usage at the time, that Evan Lewis posted on a couple of years back.
The three he highlighted were Whitman Books editions, a publisher big on juvenile books of all sorts back then. The only Whitman I have is the Zorro by Steve Frazee(1958). The other two were English editions of the books as part of a Television Favourites Library series by World Distributers (Manxhester) Limited. Unlike the Whitman Books, these were given titles other than the name of the TV series.
The Have Gun, Will Travel was Perilous Journey by Barlow Meyers(1959) and the Maverick was Boss of The Rocking H Ranch by Charles I. Coombs(1959).
I enjoyed this brief excursion back to my long ago youth(who says time travel is not possible).
Foe more forgotten books, as always, check out Patti Abbott at her blog, Pattinase.