Hi James,
I reckon, weather in Australia has picked up which is why no one replied to your post, yet?
congrats to the purchase
I assume, the "eq6 non goto" is motorized for tracking?
For imaging nebulas it is good to choose a short focal ratio scope like f/6, f/5, f/4. Short focal ratio reduces the exposure time required for good images.
Your Eq6 can handle the weight of a reflector - so you could have a look for an 8" f/5 or there abouts. They are much cheaper than refractors.
Bear in mind that you will need a camera, too

t-mount adapter and t-ring for your camera to fit onto the focuser.
focuser: depending on what the tube comes with you might want to have a different focuser, too.
A tool for collimation would be good to align the mirrors properly.
I assume you want to wait with auto guiding, for now?
So that expense can be left out, atm.
Have a look here on the Bintel site:
http://www.bintel.com.au/Telescopes/OTA/37/catmenu.aspx
They are in your budget and leave some money for accessories.
And of course the
IIS classifieds.
Hope some other ppl will help you, as well. Because I'm still a noob, too.