"I am thinking of getting an analog synth. Must be inexpensive and able to recreate that late 70s moog sound. At the moment I am thinking of the Arturia Microbrute or Novation Mininova."
Mininova's not an analog, but an analog-modeling digital synth. There's nothing wrong with that, analog-modeling synths sound just fine, I'm just pointing that out since you seemed to be particular about the Analog bit. The Novation Bass Station II, however, is an analog synth and roughly in your price range, as is the Korg Monologue. And Microbrute will *not* get you a Moog sound. None of the aforementioned synths will.
The cheapest option to get close to a classic Moog sound is software (Arturia Mini V, Native Instruments Monark, U-he Diva). If for some reason you *need* hardware, you're not getting the Moog sound south of $600-700, like a Mother 32 or used Slim Phatty, both of which don't have a keyboard so you'd need to spend a bit more. There's also the Minitaur, which is pretty cheap but is limited note-wise (as in, you cannot play notes higher than, IIRC C4) so I wouldn't recommend it as your only synth.