Marin Wolf Ridge/Attack Trail/Rock Springs all can be had for less than £500 secondhand.
All of them feature 146mm of rear travel and 12mm Maxle droputs, the later models have tapered headtubes and ISCG mounts, but some lose the Fox Float shock that works so well with the frame.
They’re surprisingly versatile in spite of the geometry and all up weight, however they’re a great deal of fun and are hugely fast and confidence inspiring on the descents. The 08/09 models came with Pikes, which suit the bikes admirably but they’re also just as happy with a 160mm fork of your choice. They pedal really well too.
Highly recommended.