Boxster 986 - oxygen sensors and idle air valve

[monopola]

Hi guys,

I have an issue with my car - it starts and runs, but sometime when I stop the engine shut downs - rpm is going around 400-500, sometime it goes back to 800-1000, sometime it shut downs.
My local mechanic does not have diagnostic software for the car, so I bought durametric, but still waiting for it.
Another mechanic check the car with Piwis and the mistakes were about air presure, so they checked the car and told me that I have to change idle air valve, both oxygen sensors and all sparks.

I am waiting for an offer, but looks like original idle air valve cost around 600-700 USD here in Bulgaria and I cant find the exact oxygen sensors.

Could anyone tell me what are the exact part numbers - what website you are using to find such things? Or any idea on the price of these parts.

ALso - is durametric good enough or Piwis is better?

Best,
Atanas