Source for U-shaped rubber grommets?

[Corporate666]

I am having an impossibly hard time finding what I want.

As the title says, I am looking for U-shaped rubber grommets that can go into a U-shaped cutout in a panel, producing a flat edge. 

I can find tons of round grommets, but the only U-shaped ones I find are from suppliers on Alibaba or custom manufacturers showing off their custom jobs.  I have searched McMaster, Richco, Heyco and a dozen suppliers I found through Google, but none of them have stocked U-shaped grommets.

I only need hundreds of them, so I need something off the shelf.  I don't have the space to put any sort of gland fitting either... it's really gotta be a ready made part.

Any tips?  Ideally a USA supplier that I can order online from.

[DTJ]

They might be called horseshoe grommets.


http://www.allstatesrubber.com/injection-molded-horseshoe-grommet/

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