This but less complicated, stood up in the back of the wardrobe you clothes are in, screw dividers in and put a bungee across to stop them falling forward
google "exhaust expander", kits are available for about 20 quid, will need to be very careful in its use though, just enough pressure to straighten the pipe without stretching it or damaging threads etc . It's how i get dings exactly like that one out of roughly handled new exhausts.
Does the tip of the CO2 containing part push in? I assume fronm the picture it replaces the piuston in the original system, so when you cock it and pull the trigger the c02 containig part slams forward into the piston head opening a valve and releasing the co2