thadword

Does anyone know where i can buy a valve, vacuum switch (as listed by lexus dealership). It is listed under egr valve vsv on my repair estimate sheet, which is priced at 118.37. I don't know which valve is which on other sites that sale lexus auto parts. I just want to see if i can get one for a cheaper price. There's a lot of valves and i don't want to purchase the wrong one. All i know is it has to do with emissions, because my check engine came on again after my egr modulator was changed. The check engine light comes on some days and then it's off other days. But i'm sure it has to do with my vacuum switch valve. So maybe it's affiliated with the egr modulator. So, any suggestions?