Have a look at Maxton there first class will make a custom shock for your bike / weight / 1 or 2 up riding, they also do a full cartridge insert for the forks, I have spoken to them and they are very helpfull with a lot of experience with Road and Racing so they know there stuff.
Regards
Yet another great alternative it seems. Don't see a chart for the R3 but that is true of most of the AM shocks listed above. Most will custom fit special orders. The prices seem better than most high end suspensions too.