I'd say the York Optical one is the standard Celestron Dob similar to
this one If so the I think you will find it is exactly the same as the Skywatcher (may even come out of the same factory), though if I'm incorrect I'm sure someone here will correct me
Have you checked out the Skywatcher prices here at
www.myastroshop.com.au or the GS Dobs at
www.andrewscom.com.au ?