Source for 1/8" wire rope clamps for EarthTainer

[tomacco]

I'm trying to build a batch of EarthTainers. For each one I need 15 1/8" wire rope clamps. I went to Lowes and found precisely 15 which then left them cleaned out. Each clamp was packaged individually. I have no idea if this is normal.

I'm wondering if someone has found a better source for these for bulk purchases. I really don't want to have to wait for Lowe's restocking cycle.

Any ideas where I might find a good supply of these?