I'm presuming you're talking about dimples for the gas block, and not trying to bubba/KAC style dimple your barrel.
If it's the first, I believe tier one armory has one or a few. Not sure if they sell or rent them but could be worth a phone call.
Yes, gas block dimples. Although I did laugh pretty hard at the idea of someone sitting in their basement with an electric drill dimpling their barrel. I think I've got a line on one but I'll keep Tier One in mind in the event it falls through.