There should be zoom lenses avaliable even for film cameras.
Anyway, imho, 24mm is already very wide on 135 film. 28mm was a common wide angle used in those times. 24mm of course is a wider variant to that.
50mm is considered a normal lens, and good all rounder
105 is considered short tele and ideal as well for portraits.
So your choice of 24mm / 50mm / 105mm is already well rounded for walkabouts.