You can use any wire with sizes:
.010" (0.25 mm)
#34, .006" (0.15 mm)
.015" (0.38 mm)
#32, .008" (0.20 mm)
.020" (0.50 mm)
#31, .009" (0.23 mm)
.031" (0.78 mm)
#29, .011" (0.28 mm)
.082" (2.08 mm)
#26, .018" (0.46 mm)
.125" (3.18 mm)
#23, .023" (0.58 mm)
Just check out Amazon or eBay and get any wire within the sizes range.