Might be stirring up a hornets nest here but the 17HMR is a poor choice for coyote. I'm well aware of people who have done it and heard all the stories, but it's a marginal performer in anything larger than a jackrabbit. Thin 17gr projectiles at rim fire speed are stopped pretty easily by a rib, shoulder blade ect.
We we did field clearing for a jack rabbit problem and used 17HMR's, only excellent shots (head, or the tiny vital zone) put them down cleanly, other ran off with their guts trailing behind them or flopped endlessly. I'm talking 100 or more jacks over a weekend. I've seen more coyotes wounded and run off from the somehow miraculous 17HMR than any other caliber combined.
I agree the .17 HRM is weaksauce on coyote, but at nighttime distances (without artificial lights), I think it would be doable, given the options. Of course, I don't think it is one of the allowed rimfires, now that I think of it. I wonder if GOAL would be willing to put together a bill to make it all rimfires; as a stepping stone to wherever else we'd like to be.
I don't know why nobody has come out with a solid lead flatpoint or hollowpoint round, or the Barnes-X, for better penetration.
Again, how much "nightime range" is required, without lights?Workable pistols, but I don't think any of them is going to carry enough velocity to stretch out the effective nighttime range on coyote the way a rifle without the stupid restrictions would.
Maybe a 15"" 17 HMR Contender pistol... could still get some decent velocities at that barrel length. 14" 17 HMR is a factory available barrel, too. Could do the same with the 22 TCM, as well. In the same neighborhood as the 22 Hornet, but based on a parent case you can pick off the ground on any range in the US. 17 HMR would certainly be easier, since I already shoot it.
Tell us about the 22 TCM. I not only know nothing of it, I've never heard of it.