You might want to take your Tiger stand and measure the distance between the lugs and compare them to the R3. I think you'll find the distance is the relatively close. I have the centerstand from the T100 on the shelf (we don't need that anymore as the T100 is always vertical anyway). I'm going to see, this winter, if I can fit the T100 centerstand to the Rocket. The T100 centerstand has a well engineered cam type over center retraction mechanism that has no dependency on external spring mounts. I might have to change the location of the actuator arm but the stand itself is very a very robust weldment. We'll see if it indeed works and if it's workable we may as they say, 'go from there'.
The centerstand for the T100 is around 150 bucks at the Triumph shop.