I just went through all this with the GT I bought from cyclingdeal for Mrs Tubbsy.
I measured the relevant bits with callipers, emailed Cyclinic and they sent me what I needed. Different frame from yours though, so I don't think the bits will be the same. Numbers look slightly oddball from not having the callipers 100% straight, but there aren't that many variations, just round up or down to the nearest standard.
I used a new shock though,
@safreek's looks like the DU bushings might be worse for wear/missing?
You might need the tool to push them out/in - I'd stump up for the service as
@Oddjob says (have to send you a message actually OJ), get it all sorted in one go.