13.3":
http
/www.p4laptops.com.au/Metabox_Prime_W230SS.htm
15.6":
http
/www.p4laptops.com.au/Metabox_Alpha_W355SS.htm
17.3":http

/www.p4laptops.com.au/Metabox_Alpha_W370SS.htm
all have the same spec, add another $10-20 and you can buy an SSD for anyone of them, though the 15.6" you don't need the extra, they are without OS's so if you need one then you're gonna have to sacrifice the SSD, but you can buy one at a later date for a cheaper price for definite.
the 17.3" gets quite heavy, the 13.3" is quite light, but you like bigger screens, weight is going to have to be for definite unless you go slightly over budget and get this:http

/www.affordablelaptops.com.au/contents/en-us/d314_msi-ge60-laptop-notebook.html
its a bit lighter, but is $200 more and doesn't include an SSD
hope this helps.