I did not realize you wanted a 6" cutout for (I'm guessing?) a 4" diameter tube with a 6" diameter base.
Mine has a 4.675" (119MM)Ø cutout. It is only 1"(25.4MM) deep. Doesn't seem like it will work.
While I could make you one exactly how you describe out of brass, it would be expensive. If you have no other luck, give me a shout and I'll see what it would cost.
If looks could kill, I'd kill your television...Primary
--Waiting for the TTB to give me my brewers notice.
Big Choice Brewing Company
OPENING APRIL 2012