Fluidmaster cistern packs.

[JCplumb]

Are £12.29+VAT at plumbfix at the moment! That's for the height adjustable fill valve AND dual button Syphon with integral overflow. Happy days.
Thought I'd give you the heads up if you hadn't already spotted it Will be grabbing half a dozen of these tomorrow...

 

[Dannypipe]

Yeah, I've always bought those. Shame the fill valve isn't the brass tailed one though. Bargain price isn't it!

 

[Billy Bob Bob]

i have 8 in stock at the moment good sellers and they dont go wrong

 

[Guest123]

Yes a good price and bought a couple the other day. The plastic tail is ok if you take your time.