Sounds go me that someone wanted to sell you a $10 can of green gas at $20 profit...
Anyway, get the AI gas kit. It includes the propane adapter and silicone oil. That's all green gas is anyway - propane with a different scent added, and some silicone oil to lube your seals. You get about 2x more propane in a Coleman can for $3 than you get in a can of green gas for $30...
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