My 223 build is based on 300 WSM action.

It did not have an extractor. I want to install an extractor so my question is what parts are needed?

My initial understanding is the following

Savage Arms Ejector Top Loading All Calibers http://www.midwayusa.com/product/117...g-all-calibers
Savage Arms Ejector Retaining Pin Top Loading All Calibers http://www.midwayusa.com/product/782...g-all-calibers
Savage Arms Ejector Spring Top Loading All Calibers http://www.midwayusa.com/product/194...g-all-calibers