Orange Five owner here, yes 26 inch, rear shock is Rockshox RP23 TF Tuned but it just blows through its travel when riding over rock gardens, jumps and drops etc.

I weigh about 75kgs fully loaded, any suggestions?

CCDB or Monarch Plus RC3 DebonAir using both .. on on the Alpine Five and one on the 26″ Five Im 90 kgs on a bad day

I should probably add that I bought the frame and shock second hand and the previous owner had the shock TF Tuned (to the best of my knowledge) and he was probably 10kg heavier than me

I was hoping there was a second hand option

Would try a medium or large volume spacer, failing that a Vosprung air can might help.

Volume spacer?

Been running the high volume RP23 on my Five with no issues at all for a couple of years, similar weight to you too. Might be worth changing to.

Pretty sure there’s a Vosprung Corset up for sale on here which might be an even better shout.

Volume spacer?

http://www.ridefox.com/help.php?m=bike&id=568

The Fives suspension curve/leverage ratio is pretty much linear, as such they are completely reliant upon the shock to provide the bottom out resistance, the larger the volume spacer the more resistance to bottoming out. 90kg here and run a medium on my 2011 Five with RP23, they can be removed/fitted in minutes with removing the shock

Corset air can

http://www.tftuned.com/mobile/vorsprung-corset-air-sleeve/p3135

coil the bitch