KB hood mount rubber for gauge

[laws69cars]

Does anybody know where I can pick up this rubber grommet for my gauge. I have the complete set up minus the rubber so water gets into the gauge. I attached pics so you can see what I need any help would be greatly appreciated.

 

[Phoneguy]

i would think an old innertube and an O ring would fix that....

Bryan

 

[laws69cars]

Honestly a good idea I don't know why I didn't think of that.. I'll see if anyone happens to have a extra 1 if not I will definitely give it a try. Thank you for the idea...