No ammo listed Andrew, but for break in on my Pistols I try to run a few boxes of some 124 grain ball ammo. The G3c is rated for plus P pressures so odds are good that whatever your looking at will do just fine.
Last time I stocked up on 9mm ball ammo it was Blazer Brass 124gr, which I've saved about 500 rounds just for break in of new pistols, though I've also used, Federal T&P, Seller and Belliot, and armscor.
I personally stay away from steel case in my Pistols, but if you clean your pistol regularly the red army standard in stock at buds would be ok.
Or
https://ammoseek.com/ammo/9mm-luger/-handgun-124grains?ca=brass

Andrew, virtually any new SAAMI standard pressure brass cased ammunition is fine for break in. Just follow the break in process in the Owners Manual and you will be fine. For the money, I highly recommend Target Ammunition : ammoshoponline.com/shop/caliber/handgun/9mm-luger/9mm-115-grain-fmj-norma-range-training-qty-50/ ------------------- And for Self Defense : https://southernmunitions.com/shop/brands/sellier-bellot/sellier-and-bellot-9mm-115gr-jhp-50-round-box/

right now I would try any ammo I can get at a decent price