timing belt on subarus is 4 years or 100,000km whatever comes first. changes slightly with 07 onwards. not that hard to do, belt should be 150 or so genuine + 2 hours labour for dealer to fit. Have seen the results of snapped/stripped belts, its not good.
can be done without special tools yourself if you know roughly what your doing.
DANG! drive down to vic and get it serviced, it'll be cheaper including petrol money!! unless you got any extra work done thats waaayyy to much!

