Just a heads up, Rangers don't have struts. Just shocks and springs.
Head over to your local auto parts store...O'Reily, Napa, Carquest, etcblahblahblah. Many report decent results from the cheaper shocks like the lower grade/ie cheap level Monroe, Gabriel, and KYB. Most shock companies offer a budget shock, a mid range, and a high range with progressively higher prices. You do kind of get what you pay for....
However I will say any new shock is better than any old beat up shock.