LP FW flipper system wanted

As in the title i am after a LP FW flipper system, I know with the use of ebay and other sources you can build these fairly inexpensively now adays. My problem with this is i don't have a huge understanding of these setups and don't want to shell out l hard earned cash on parts that may ( and with my luck) not be compatible with each other i have read though many Pneumatic systems ie davini's understanding pneumatics but I feel personally buying someone's old complete or near complete setup will be my best bet for understanding. I'm not asking for the worlds best setup either just something that someone no longer needs or has now upgraded and wants some cash for.

Many thanks all.

well I have an older, short stroke ram, firing valves, connectors and pipework you are welcome to, but you would have to get the other necessary gear for the system (Dump valve, PRV regulator and main tank/buffer)