Steer well away from gas only shocks (monroe, gabriel etc) as they have too much rebound and you will wheelspin and skip over bumps etc especially in a ute with the lighter rear end.

Kyb make some good cost effective shocks.

Also look at shocks from different cars, many will fit, Ive had bilsteins from a 320i bmw in my sedan, bit too long though, also SAAB front shocks in the rear as they are real short and work well also very high quality.