Leading on from my above post, this head:
[url="http://basschat.co.uk/index.php?showtopic=81854"]http://basschat.co.uk/index.php?showtopic=81854[/url]
...and this cab:
[url="http://basschat.co.uk/index.php?showtopic=83341"]http://basschat.co.uk/index.php?showtopic=83341[/url]
would make an immense cheap, powerful and loud rig. IMO, it's exactly what you should be looking for given what you're looking to buy and your budget.