I have been searching for 6.5 Carcano ammo now for about a week and could really only find one affordable source. SGAmmo.com has it from $18.95 and $19.95 per 20rd box. You have to purchase at least $79 from them to ship it though.
The PPU ammo the OP references is labeled as topped with the correct diameter Carcano bullet. Just be mindful some 6.5X52 PPU ammo is loaded with .264 bullets. The rounds will go bang just fine, but accuracy will be about zero.
My recommendation is to make sure one has the correct ammo for the rifle’s bore and in the right bullet weight. In my experience bullets lighter than about 150 grains will shoot, but not well in my relic rifles.