I have two Nikon Buckmasters on my Cz's. Both are >17s. One is a 4.5x14 which is good and one is 6x18 which is better. Both very clear and excellent for the money.
My Cz's are not overly fussy on ammo, as said above. Just give the barrels a few shots to adjust.
There are few bargains on ammo. If you can find last years stock and an honest supplier you may be able to get it a little cheaper. Practice with a .22 and blast gophers with the .17. Its cost effective.