These Stainless Steel (304 grade) Screw Eyes are great for making swings or hanging toys from!
Some ideas:
Drill a hole at both ends of a perch, then add a screw eye at each end, loop a long piece of wire into the eyelet with pliers at each end to make a swing.
Drill a hole into your birds perch, add screw eye and then hang your birds toy from the perch
See size measurements under Additional information.