I wondered if it might be Pommerhelix mastersi (Cox, 1864) n.comb. by S.A.Clark (2009): A review of the land snail genus Meridolum (Gastropoda: Camaenidae) from central New South Wales, Australia. Molluscan Research 29(2): 61-120. Available free online. Clark reports P. mastersi (formerly Helix, then Meridolum mastersi) from the South Coast at numerous sites between south of Merimbula and Jervis Bay. I found a similar specimen recently inland from Batemans Bay.