OK - you guys are a bit shy.
Some more details.
The gun I would like to enhance is a 10 Bore Paradox. It is a hammerless back action configuration. Lots of beef. The rifle is posted in the DR photo archives.
Last year Champlin sold one that had extra .600 barrels made for it by Holland. I had seen a similar one with .577 barrels.
My other option is a new set of chopper lump so no monoblock would be needed.

Bramble - how about across the pond there!!