According to the handbook there were
Line 12 1/2
Line 11
Comb 12 1/2 x 12 (horizontal format)
Comb 12 x 11/2 (vertical format)
Line 12 1/2 (actual 12.4) from 1876 with large holes
another machine same gauge with small holes from 1902.
The book mentions the various stamps which used that gauge.
Line 11, 2 machines from 1902, one small holes, the other larger blunt teeth.
Comb 12 1/2 x 12, 2 machines in 1901 (actually 12.4 x 11), 2 new machines in 1909 (11.8 x 11.5)
It is a complicated issue re. perfs., I suggest you get hold of the literature and not rely on any catalogues which are only basic.
I do not collect WA but have the book and also the other reference books by Mogens Juhl but can't locate them.
There is a society which specialises in WA, The Western Australian Study Group,
http://www.wastudygroup.com/They produce a fine magazine on WA, The Black Swan, you should contemplate joining,
Pagoda