Target cam

I can't speak for them but I've been eyeballing them...

 
I used the GSM Bullseye target cam this last weekend out to 1260 and was impressed. easy set up, battery lasted all day, image quality was good. Advertised distance on the "sniper" model is out to. 1 mile
 
If you are just looking to see if you are hitting the target at long distances you might look at the T1000. Velcros to the back of the target and you can see it for a long long way. Was going to get a cam a while back but found this was better for me.