Lance recommended the Old Man Emu kit, says that it is springs and shocks and other parts and in the usual configuration would give about 1 inch of lift (maybe). He emphasized that springs do wear out, and Land Rovers usually need new springs around 100,000 miles.
The best stock options for the Tacoma seem to be the Bilstein HD or the Bilstein 5100 series. The rear shocks have a different left and right. The passenger side rear shock is about an inch shorter. One guy measured a length of 12.5 inches compressed and 19.5 extended on the passenger side, and about an inch longer on the driver side.
Links:
Uncle Tom's Tacoma pages / tom@mmto.org