Unless you have to have a new one why not check into any swap meets that might be happening in your area. Trainers can sometimes be had for next to nothing and I have seen complete setups for $100-$125. If your flying off grass try to stay with a good ballbearing 46 on the 40 size planes. All those trainers recommended in the previous posts would work fine.
One of our newer members just showed up with some kind of multiplex trainer from tower that has two different wing dihedral set ups. One for a flat wing and one for a wing with dihedral(sp) and they can be changed back a forth. the plane flys real well.
Fred