Again, this is a tentative post just to see what's out there. But I could be tempted by the right Dale
I'm tempted by a F Series (or even a Scalpel if I'm lucky!) with a spec similar to my 456. I'd prefer a Lefty fork, but a Headshok would also be good. Size needs to be Medium (16-18")
Here's the spec of my 456C:Frame: 16 inch On One 456 Nude Carbon, very good condition. Tapered Headtube. Stealth decals
Forks: Magura Menja 130. PERFECT working order and VVGC but MIGHT benefit from a service as I don't think they've ever had one.
Headset: Hope Integrated (1.5" with a 1,1/8" reducer in the bottom). Perfect condition.
Stem: Crank Brothers Cobalt 2. Perfect condition.
Bars. Crank Brothers Cobalt 2. Perfect condition.
Seatpost: On One Twelfty. Perfect condition.
Seatclamp: Hope. Perfect condition.
Saddle: Charge Spoon. Perfect condition.
Wheels: Hope Pro 3 SP hubs laced to DT XR4.20 Rims. Hubs are perfect and rear freehub is LOUD!!. Rims are VVGC.
Tyres: Schwalbe Racing Ralph. Pacestar Compound. VVGC. Tubeless ready.
Rear Mech: XT M770 Medium Cage. VVGC.
Front Mech (not pictured): XT ?M770?. VGC.
Shifters: XT M770. Perfect condition.
Chainset: XT M770. VVGC.
Cassette: XT M770.
Brakes: XTR M970. VVGC. Spare set of VVGC levers included (very hard to get hold of and perfect for spares or replacements).
Brake Rotors: Alligator Windcutter. 180/160.
As you can see, it's a pretty decent spec. I've never weighed it, but I'd guess at around the 24lb mark with pedals.
I'd also think about a frame/fork swap.
Pics (note - these were taken when the bike was first built. The spec now reflects the list above):