You can get a used Meade LX90 or similar for around $2,000 - $2,500. You may want a focal reducer as well for prime focus photography (an f/6.3 reducer has just been listed on the Buy/Sell Forum).
Depends on what kind of scope you want (Newt, Schmidt-Cassegrain, refractor). Bintel have all the SkyWatcher Pro scopes on special just now with GOTO equatorial mounts.
www.bintelshop.com.au
Lots of people on this website use Newts for imaging. Check out the Images and Photography forums.
Morton