[Source] 18k old Chain and Wire

Question on a source for 18K - I have always worked with sterling
silver and copper, and have been out of the metalworking arena for
quite awhile. I am getting my shop set up again after a very long
hiatus, and after I ruin a few feet of brass getting familiar with
some of the techniques again, I would like to start incorporating
small amounts of 18K gold in a few designs. I’m starting off very
simple with some earrings and looking for the most economical source
for a small amount of 18K wire and chain - like a foot or two.
Obviously I’m not going to be getting any quantity discounts, so my
first thought was Rio Grande, but wondering if anyone has a
suggestion? I have always bought sheet metal and wire from my local
jeweler’s supply, but have found Monsterslayer and some less
expensive sources for silver in the meantime. Just not sure where to
go for gold.

Thanks in advance for any suggestions!