1676, originally in ref. to N.Amer. Indians.
scalper"person who re-sells tickets at unauthorized prices for a profit," 1869, Amer.Eng., originally of the unused portions of long-distance railroad tickets. Probably from the verbal sense of
scalp (q.v.).; perhaps the connecting sense is the bounty offered for scalps of certain
destructive animals (attested in New England from 1703) and sometimes Indians (i.e., having only part of something, but still getting paid). Some, though, see a connection rather to scalpel, the surgical instrument.