I've never seen the originals- I know I'm a youngin!
Gumby originally hit the airwaves around 1956 I think, as a segment on NBC's "Howdy Doody" program. The character was created by Art Clokey, whom previously produced a rather non-objective film using the plasticine medium called "Gumbasia" (some PD DVD's have this on, and is probably the only best reason to pick those discs up), which attracted attention from the network to pay for a simular thing to show during the program or whatever.
The earlier episodes used stock music that was from the Capitol "Hi-Q" production library that often gets credited to "John Seely", whose name also popped up for a few Warner Bros. cartoons produced in '58 that resorted to using the same music when a strike occured with studio musicians then. Hanna-Barbera also used the same stock library for the music in it's early cartoons as well.