Need replacement wifi antenna

I f'd up and pulled my router of the shelf when I snagged the wires. I have since fixed the wires so this cant be repeated but now I need replacement antennas for my Asus AC68U.

Wouldn't mind a little more range but I know buying 1568db gain antenna's is not going to let me get better signal in the next room.

Should I just try to find some asus ones on ebay or is there another brand that will work well?


Thanks Guys