Greek Keys Please

I've been seeing Greek key trim everywhere: pillows, curtains, upholstery...  I'm thinking about adding some to my plain white living room curtains, but it sure doesn't come cheap.  Many of the sources I found have it listed for upwards of $15/yard.  And with four curtain panels to trim out, that adds up.

Here are a few of the more reasonable sources I've found:

MJ Trim.  Seems to be the go-to for Greek key trim.  At about $10/yard and with lots of color options, it's a pretty good option.

This etsy store.  Some of their trim is priced as low as $2/yard!

Hobby Lobby.  The trim above is $7/yard, but there is always a 40% off coupon, so it comes in closer to $4.  In thicker widths this is the only colorway online, but maybe they have more options in stores?

HL also has thinner widths (3/8") in several different colors for just $.50/yard.

Any other good sources that I missed?  I'm still on the hunt, so I'd love to know!