Well I ended up buying a pair of JBL TR125 speakers and stands, and a Phonics Powerpod 1062 with 375 watts per side.

Can I thank everyone for their help especially Richard Bridge who was incredibly helpful to me and whose support was way above the call of duty :)

If you're ever in North Yorkshire come and find us and I'll buy you a beer.

I now have it learn how to use it and will probably be starting a separate thread later for a crash course in setting it up and getting a reasonable sound out of it so that I roughly know what I'm doing on Monday when we play...