Any lead core .358 diameter bullet {rifle or pistol} can be resized to fit your rifle. Also, you can use 9mm pistol bullets for plinkers and such. And, you can size 9.3 bullets down from .366 to 35-whatever yours actually slugs. Just make sure you have enough chamber relief for the cartridge neck.

I size .375 cal bullets for 9.3 rifles and they work just fine.

There are MANY bullets available for your 9x rifle.