Interesting comment. I am not aware of any official restrike of Australian pre-decimal proof coins, hence the question of "original" proof coin is invalid question.
The 1957 proof pennies were officially restruck (in 1959). Only 470 "originals" were produced. The originals have a mirror finish (like the 1956 and earlier Perth mint proofs) while the restrikes have a brilliant finish with a matte relief (like the 1958 and later proofs).