If you liked the sound of the Peavey their MiniMax 500w amp is under £400.
I like similar sounds as Ampeg SVTs and I use Ashdown amps, given the brief I’d recommend the Ashdown RM500 EVO2. It has good flexible eq, drive, compression, is loud and sounds great. Of all the Class D amps that I’ve had (a good few) it’s the one that has the “weightiest” sound.