
Paul
Do you always shoot at the same distance? Variable power scopes are variable for a reason.
Effective range depends on the ammo. .357 ammo is available from Buffalo Bore, and a couple others that is effective at 200 yds. Or you can roll your own. Anyway, just a point of interest. I have dots on other pistol caliber rifles that I like, so I'm pretty sure one will work for you.
I have both Vortex Striker 1-6x24 and a Leupold 3.5-10x40mm.