Tube clasp construction

[Petal]

Hi everyone,

I wish to fabricate my own copper and silver tube clasps, with a spring mechanism, so it clicks into place like this one https://www.cooksongold.com/Findings...prcode-NVF-211 The wire inside is .5mm thick.

Is there a particular type of wire I'll need to source, or do you knowledgeable people use something else instead??

thanks in advance