Carcanos were made in 8mm Mauser which is 56,560 psi. As to if the action is strong enough for 6.5 Creedmore I couldn’t tell you. It is a strong rifle for it’s weight. You would likely need a new barrel as a 6.5 Carcano barrel isn’t .264” and it would have to be set back and re chambered if you were to try rechambering the rifle. Plus you would have to modify the bolt face/extractor as 6.5 Creedmore is bigger. And then there is the issue of the mannlicher action which would have to be modified to work with the larger cartridge.
The Arisaka should be able to handle those pressures, insanely strong actions, stronger than a M98 Mauser action. Issues with using a Type 38 is 6.5x50sr is a semi-rimmed cartridge so it likely needs modifications to the bolt to function properly. A Type 99 would be a better option as 7.7x58 is rimless, again requiring a new barrel.