Back to the OP question:
PCP or CO2 are going to be the way to go. The hottest spring pistols only deliver "700 fps" with lightweight alloy pellets that are useless for anything over gophers.
In spring guns, top contenders might be the HW-45 (or Beeman P1), RWS LP-8, or the Browning 800 Express (most cost-effective). Spring pistols are hard to shoot well and never deliver the advertised velocities with hunting weight pellets. None of them are adequate for coyote.
PCPs are amazing, and have come a long way in a few years. The very top of my list is the Crosman Marauder Pistol, often known as the "P-rod" on the forum cited earlier. I have one in .22 and it will produce a silent 660 fps, very accurately. Downsides are size (long), and the fact that you need a tank or specialized pump to charge it. Also the fpe of this gun is not adequate for coyotes, although it will kill rabbits, squirrels, etc well out to 25 yards. It comes with a shoulder stock and frankly I only use it in this carbine mode.
Evanix has the AR-6 PCP pistol that is a hammer. It is also large-ish, and LOUD, being unmoderated (this is by comparison to other airguns, not powder burners). If noise is not much of an issue, you should look this one up.
A new and somewhat spendy alternative would be the TalonP pistol in .25 with 50 fpe of power. It will kill a coyote. It is also LOUD. I am somewhat interested in this gun but I will let others work out the bugs and get some miles on them.
PCP rifles can easily take coyote and larger game, but you asked about pistols.
Know-it-all heard from! :laughing: