I had my rib re-tubed at henshaws last year. Excellent workmanship, excellent service and a top notch result. Around the two and a bit grand mark for mine, just a basic re-tube with fittings including 4 handles/cleats and D section rubbing strakes. Drive in drive out. chuffed to bits. I believe they do collars for alot of the rib builders in this country and abroad. I spoke to lots of people before I had it done and almost everyone said they were the best in the business!
Hope this helps.