Replace Rear Middle Seat-belt

When I bought my car the middle seat belt in the back was missing the metal piece that buckles into the buckle. It has the bottom buckle piece and the belt itself but no silver piece to attach. So my question is, can I use any Toyota seat belt to replace it or is there somewhere I can get it without a huge charge? Or should I just suck it up and take it to the dealer and let them vampire my money until I am left a cold corpse on the ground?

Thanks