Hi Wardy,
I have just sold my X Country to a member of this forum and have a Hyperpro rear shock which I purchased a couple of years ago form the UK distributor Calsport which I plan to list for sale with other items at the weekend. Its the slightly lower 320 mm shock with a 95 kg purple spring as shown in the photo attached.
please send me a DM if this would be of interest to you.