I agree with whoever said go with the combo.
Unless you're planning on playing some pretty big venues you won't really need all the power of a half stack (at least not a valve one).
That or go for a 2x12 cab rather than a 4x12.
As for recommendations, I'd check out the new Randall valve amps, the module ones. I think you may be able to get one with your budget and apparently they'll simply blow your nuts off (I haven't had a chance to play around with one yet.)
Keep checking Ebay and Adtrader etc and you may come across a used Peavey 5150 combo, Triple XXX or even an old Ultra, all of which would be great for metal.
The Ashdown Fallen Angel would quite easily fit your budget, but it there seems to be a bit of Marmite issue with this one, I know loads of people who swear by them, but then others who think it resembles a wet fart.
Or if you're willing to put in some time and hope for some luck you may be able to get a small rack setup. I just grabbed a Hughes & Kettner Access Preamp for £130 (absolutely awesome btw) and should be getting a pretty good deal on a second hand Marshall 20/20 poweramp and 2x12 cab, for just a little over your budget.