WTB: Lightweight Extension Springs (Dallas-Ft Worth Texas)

[SteveJ34]

I am trying to help a family member with an art project where he needs to source "lightweight" extension springs.

They are to be used to dangle a very lightweight piece of art so that they are 'bouncy' so what is needed is a very lightweight load spring.

Need something that is 18" or so that extends out 24" or so when item is attached.

I know what I am looking for but am limited in my knowledge of how to 'spec' something from an online source to make sure the spring is lightweight enough.

I am in Dallas-Fort Worth metroplex and often have good luck finding such items at Arlington Ace Hardware. They have a large assortment of extension springs but nothing that is quite right in that most are designed to hold more of load/weight than what I am looking for and most were not near as long as what is needed.

Any suggestions on where to look or ideas for how to interpret the specs given from an online retailers?