^^^
IMO it would not really be worth driving to the breaks an hour or so north of Perth... they will still be too small.
Best bet is the South West... there's a couple of 'small swell magnets' down there that will still deliver shoulder to head high waves on the smallest of swell. However the tides will be critical...
There's a couple of well known breaks around the Dunsborough / Yallingup / Margaret River region that I would be checking...
EDIT: Red Thumbed for offering non-specific and general advice regarding a 20km stretch of coast 'renowned' for its surf breaks...
