[Milsurplus] WTB: Insulating washer(s) from AS-3900A/VRC SINCGARS vehicular antenna

[Jack Sullivan via Milsurplus]

In moving this antenna recently I apparently lost one of the flexible insulating washers that prevent the top section from shorting out to the base. I'd like to sell this antenna & have listed it on eBay. However I'm reluctant to stick someone with an incomplete & likely not working antenna. I'm interested in either buying one or two or getting the physical dimensions & material spec so I can try to source it commercially.

Thanks!

Jack