Budget 2-3k
The legends at the AVSForum recommended a PA style speaker like the Behringer B215XLs.
You're not going to get much love around here for the Behringer crap boxes. Yeah, they make noise, so if that's all you care about, it's a cheap solution. But, cheap boxes generally mean more distortion. Distortion can cause ear fatigue and become quite annoying even at low volumes.
From a 'pumping' standpoint, you can either hang big boxes, or even better would be to hang much smaller boxes and add a sub into the mix. It's a gym so you don't have to go super crazy with it. My experience in gyms is they generally go the 'cheap' route and it just never sounds all that great, especially when they crank it up.
With only a 2-3K budget you may have a hard time putting something of quality in, installed correctly. $2-3K might be enough for rigging hardware and the installer.