I used a Mackie MS1202 and got awesome sounding mixes with it. Should be able to find one used for about $150 - $250 US. Try not to pay more than $200. Good luck.
By the way, at that price range you won't get sweepable mids and maybe not even a regular mid EQ. Just Hi and Lo which are usually shit except on the Mackie. Oh, and maybe a couple of others that may be mentioned.....
Good luck.