Wobbly passenger bucket seat in 94 Extended Cab Sierra

[Fireball5657]

Recently replaced the old worn out seats in my 94 ECSS sierra and also did an upgrade to a power drivers seat, but the passenger side seat rail is very loose. So could I just replace the seat riser? And if so, what years will work? And final question, what models should I be looking at to get the easy access for the rear seat?