No transplants from any other bikes, only the aftermarket shock range such as:YSSHagonNitronOhlinsBitubo
etcYou could also rebuild the standard shock and add a Hyperpro spring, but it'll still have a standard shock's valving.
For what it's worth, the R6 shock conversion is well worth doing providing you're not a stick insect or a bloaterEDIT: I think Luke/ Devilsyam sells all the parts needed for the conversion