For compatible shocks check out the Shock Swap Info spreadsheet
on Google. You want one with a 90 degree reservoir.
For the correct spring rate for your bike and body weight, check the Penske Spring Application Chart
In my case (USA) the ZX14 shock was much cheaper ($50) and I swapped out the rock hard OEM spring with a properly weighted Hyperco spring ($80). Had to invest in a Shock Spring Compressor
tool ($35) and a Racetech spring adapter collar
($4, item no. SPSC B5855), but my shock feels perfect now. Oh, and I needed to cut about 2mm off the bottom link bolt as it was touching the dog bones aka shock linkages.