If you already have a 144Hz monitor, don't bother with a 240Hz one - HardwareZone.com.sg
Amazon.com: ASUS ROG Strix XG248Q 23.8” Full HD 1080p 240Hz 1ms Eye Care G-SYNC compatible FreeSync Esports Gaming Monitor with DP dual HDMI : Electronics
Dell AW2720HF 27" Full HD (1920 x 1080) 240Hz Gaming Monitor; FreeSync; HDMI DisplayPort; Flicker-Free; IPS Panel - Micro Center
AOC C27G2ZE/BK 27" Full HD 240Hz Curved Gaming Monitor - Laptops Direct