Strange Noise - please help
 

I found out what the strange noise coming from the front passenger side is coming from. I thought it was the fuel pump but it turned out to be something wierd. The noise is coming from a hose in the fuel door opening that is controlled by a solenoid that turns the vacuum on and off. It is really like a horn effect. I am told by my mechanic that the two solenoids need to be replaced. Does anyone have a source for them besides paying an exhorbitant amount from a dealer.