Billyd - not a bad price. I paid close to $200 for a new valve alone. I'll give them a ring about the canister. WOT - these are emissions components - but for the fuel system, not the crankcase. Basically, the canister scrubs the fuel vapor from the fuel tank and feeds it back up to the intake for the engine. When the valve goes bad, it allows the fuel vapor to feed into the engine without any control - basically, it affects idle, but not much else - the valve gets stuck open, it is normally closed.
Built... Not Bought 