Just run on down to your local dollar store and look over the chains and necklaces in the so called jewelry department..... Maybe $2.00.........Hmmmm, no luck, too much?
Okay , then check out the thrift or goodwill store........ how about .29 cents to .59 cents? I have dozens.
Just use your common sense as to the size and style. Multiply the scale times the actual size of the chain you are looking at.
(35 in 1/35 ..... 1/16 dia. chain would be 2.1875" in real life and in 1/48th it would be 3.48"..........you need something really tiny)
That's what I used on this one.