whatever your gun says dont go any higher than that. Your air cylinder (the one you fill from) can go to 300 BAR. Buy a new one as you dont know the history of the second hand ones (well thats just my opinion) Its 300 BAR if that goes and your next to it. It will be a closed casket.
http://www.underwaterworld.co.uk/aca...g_Systems.html
Charging kits. They used to do 12 ltr 300 bar bottles for £190 but they seem to be gone now