Hammerli International -215 must haves

I have decided I NEED a Hammerli. I have it down to 2 pistols a International or a 215 that they say is 97%. What spare parts are must haves? I do have a couple of back up guns if I need but would rather be prepared in case something happens and do not want to be down to long searching for parts.
Does anybody have the link to the 41 magazine mod? 

Thanks

Several recoil springs.

Extractor, spring and pin.

Firing pin.

Mainspring.

*Maybe* transfer bar spring and slide release spring.