I had excellent results with Treadwell. I sent them the hulk of the single barrel carb original to the carrier, including the govenor, and they totally rebuilt it. Even the Govenor.
Then, then put it on a V8 test motor and set up the adjustments.
All for $98.00 USD
http://www.carbsandkits.com/tc/treadwell.html
They also have European makes.
They now know what a bren carrier is if you ask them!
Cheers,
JIm