40MM gas/co2 grenades 6mm - leaking or in good working order

Do you have 40MM gas/co2 grenades lying around, not being used.
Or are they leaking and you can't be bothered.

Preferred brand is Madbull, 
Preferred propellent is CO2.

But give me a shout of what you have and we might be able to work something out. 

No 8mm
No 40mikes
No 68. cal 
No Taginn