Without getting into debates about drivers, this is the amp I use, and rate highly. 500w per side at 8ohms, 750w at 4ohms. With your cabs, unless the new drivers are 4ohms, you'll get the first figure.
Until recently, I think this chap had them cheaper.
http://cgi.ebay.co.uk/C-Mark-MR2450-...d=p4634.c0.m14
This is a tad cheaper, but not as nice IMO
http://www.ukdj.com/index.asp?PageAc...D&ProdID=10475
Snap
http://www.ukdj.com/index.asp?PageAc...D&ProdID=21586
And don't forget Thomann. TA1400 I think.