Replacement Optical Drive bracket or fastener for Dell XPS L702x

Hello

I regularly remove the optical drive of my DELL XPS L702x to install a 3rd Hard Drive in a caddy.

I've lost the piece that screws into the back of the optical drive and onto the chassis to hold the optical drive in. I was wondering if anyone new of the part number of that piece or of a way to obtain a replacement. I seen that little piece used in other laptop. I just can't fine anything online.

Thanks.