Of course it's going to depend on the specific .410 action you use. Some have Purdey bolts and a third fastener, so ought to be pretty strong lockup. Still might not be a lot of beef in the action itself, though.

I own and have owned a number of small bore double rifles, and from my observation, the petite ones are on 28 ga. frames. An example is my Auguste Francotte 9x57R sidelock ejector.

The frame on that rifle matched the dimensions of a 28 ga. J.P. Sauer I used to own, including the firing pin spacing.

On a smaller .410 action I would limit pressures to something like .32-40, .30-30 or the like. You would have to measure the firing pin spacing to see if that limits the size of the cartridge head you are considering.

Curl