Felix Leiter was “sandy haired” Texan.
I read all the books back in the 60’s or maybe early 70’s in paperback. I would have sworn Leiter was described as red headed but as soon as I read your post, it hit me that you were right.
Also had forgotten the part about his being a Texan but you are right about that too. Also recall him (Leiter) saying he was an ex-Marine and Bond being impressed.