Hi Yorgous, it definitely sounds like you want an HX or dual boiler machine so dont bother with the Silvia. Your budget certainly gives a fair bit of choice of some quality equipment.
A dual boiler has 2 separate boilers, one for steam and one for coffee. as far as I know there is only one machine available in your price range - Expobar Minore III. Very popular machine with built-in PID control.
A HX machine has one boiler but the design allows you to steam & brew at the same time.
There is a good explanation between the 2 types on this link (its a commercial link but overseas and do not sell to oz, so hopefully this is ok with mods)
HX machines you may want to consider include:
VBM Domobar Jr
Wega Mini Nova
Shuttle (?? new machine, waiting on some reviews)
Nuova Simonelli Oscar (Cheapest option)
Im sure there are others which could be added to the list, particurlarly some more expensive machines which you may be aqble to get cheaper as an ex-demo.
Best bet is to get in touch with one of our many fine sponsors.