Workshops-
Have a word with West Racing in O'Malley St. Os Park.
They are performance car specialists and you see a wide range on the shop floor from mega-V8s, to ultra-souped Daihatsus, to the odd vintage show car that you are not allowed to breathe on. They have several WRX regulars as well as me.
Otherwise, see the workshop thread as Soksta points to above.
Personally, I would use any of those in preference to a dealer.