The Collaborative International Dictionary of English v.0.48:

Saver \Sav"er\, n.
   One who saves.
   [1913 Webster] Savin

WordNet (r) 3.0 (2006):

saver
    n 1: someone who saves something from danger or violence [syn:
         rescuer, recoverer, saver]
    2: someone who saves (especially money)

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "saver":
   Audubon Society, National Wildlife Service, Sierra Club,
   conservationist, conservator, deliverer, economist, economizer,
   forest ranger, game warden, keeper, lifesaver, preservationist,
   preserver, ranger, rescuer, safekeeper, savior, taxidermist