I've shot some magnums from my Pietta revolvers. Probably something like 30 to 40 from each in total over the years I've had them. I've got two because I play in Cowboy Action.
As mentioned above the guns are proofed and will easily handle the pressures. But I feel, correctly or otherwise, that if I were to shoot a steady diet of them that it's quite possible that the guns would shoot themselves loose in fairly short order. Things like the hand and notches on the back of the cylinder and the notches for the bolt would likely wear or become sloppy from peening from the extra energy and thus the lockup at full #### might suffer.
But a few on rare occasions such as you're suggesting and keeping the total number of them in mind certainly won't break the gun unless there's a fault that would have shown up already. And if it was that close to breaking something then you may as well get it over with... And besides, you KNOW you want to....
If it helps at all keep in mind that full 158gn loads are somewhat more gentle to the gun than some super light bullet that rips out of the gun at some super high velocity. Your hand may argue that but it's a fact that it's the bullet speed that is hard on the gun itself. Look at the S&W K frame magnums and how it was the super fast 105gn bullets that is the agreed on cause of split forcing cones.
Also if you shoot primarily 38Spl casings then be sure to clean out the crud ring well before you shoot any magnum loads. A little from a session before shooting the magnums isn't an issue. But if you already have a fairly thick ring of buildup such that the magnums become pinched as you load them then that's way too much.
If you are loading your own ammo take note that you can load your own Magnum loads for a fraction of factory magnum loads. And the added cost is like two cents worth of powder and a little more per bullet as you'll want to get some jacketed bullets for the magnum loads. You can shoot proper hard cast bullets but it's not always easy to find the correct alloy bullets correctly hard cast. Easier to stick to jacketed or at least plated like Berry's or Cam-Pro.