I was having the same problem. I installed Marlin's Heavy Duty Shifter Seat and Bushing and this fixed the reverse problem. It also made shifting the truck feel like new. My wife will even drive the truck now. Not bad for $16 plus shipping and ten minutes of labor.
The part numbers are as follows:
MC-10077, Heavy Duty Shifter Seat, All Other Toyota Applications, $10
MC-10078, Shifter Socket $6