360 magnum-budget cam upgrade on stock long block? Opinions?

So I'm waiting for Zcode to release his twin screw kit and don't want to spend any money on a TB or intake since it will be replaced with the TS.

My water pump and timing chain look original at 175k, figure that's a good enough excuse for a cam swap. Currently have a tuner, headers, air hat, and exhaust.

Going to keep the stock unported heads and kegger, so need a cam that will work best with that setup. For a 98 Grand Cherokee, weighs around 4400lbs with 30" tires and 3.73 axles.

New to domestics but if I understand correctly all I need is a cam and valve springs correct? I think I'd also need pushrods with a regrind cam but what if I used a new cam? Stock unported heads, don't want to take them off the truck. Not losing oil or coolant, maybe previous owner took care of it. Bought it from a charity so no idea.

Suggestions on where to buy the parts or what cam to use? I think the kegger falls on it's face after 5k rpm so no point in revving higher but I'd like the cam to also work well with a twin screw. Would like to spin it up to 6500 rpm with the TS. Since my jeep is a 2.2 ton pig with a 1st gear that will hit 61mph at 6500rpm and over 100 in 2nd, I think I need a cam that will move peak torque higher up, but idk.

Thanks for any help!