Geraint: I have recently purchased several Gibson LPs, I own an Epi Elitist Les Paul Custom, and I have owned several Epiphone Les Pauls.
Here is the skinny.
In this market I would go for a used Classic or Standard. Gibson MIA. You can pick them up for 1000 to 1400 depending on year and model.
I have a Studio in fireburst, Classic Gold Top, and a Standard in Tobacco burst. The Tobacco is a 96 and it is beautiful. The classic has the 60s neck and the Studio is a 50s neck. The Studio was supposed to be gone today on a trade for a 2008 Marshall DSL100, but the guy can't get away from work.
The only reason I am trading the Studio is that the price point I paid falls in line with what the guy wants for the amp, and I have lots of guitars.
If you want to go a little less money, the Tribute looks like a nice guitar.
It has the Gibson 57 classics, and a 60s neck. I think they are going for 799
I am not sure about the 59 I have only recently heard of them.
I have and Elitist, which was made in Japan with the Gibson pickups. It is an amazing guitar. Also the Korean LPs by epi from prior to them moving to China are exceptional buys. The Custom is really nice. The Chinese ones are not as nice IMHO.
As far as pickups go most of the Gibsons will have the 490/498 pickup set and they are really one of the nicest that Gibson makes. All the hype about Burstbuckers and 57 classics etc is just that. The the 490 neck is the same output as the BBs or 57s, the 498 bridge is 13.5 and is great for solos etc.
The BB pros and the 57 Classic plus are a little hotter. The PAFs that they are trying to copy were both in the 7 to 8 range and hard to tell apart when playing.
Most of the Epi Pickups other than the ones that have Gibsons in them from the factory are an offshore version of the 490/498s.
I learned my lesson a long time ago. If you buy a clone you will always wonder what the real Gibson was like and lust after one. If you can get a decent buy on one go for it, you won't regret it.
The Classics are often overlooked, the 90s classic Plus are excellent guitars and were actually more expensive initially than the Standard. They have a really nice flamed top. Normally the Classic is a plain top.
If you have any questions just PM me or email I have lots of experience with them.
Also the Epis LOOK like a Gibson, and most guys who own them will say they are as good, but they are not. The maple cap is much thinner, and the electronics are terrible. The pickup selector switch on them is just brutal.
I have changed all of mine including two Sheratons due to failure.
The Gibson electronics are much cleaner and the guitars are a lot louder, and the pots are more precise when adjusting.