As John said in that camaros.net link, no Camaro was ever built as RHD. I'm sure I've seen that English Camaro in the eBay ad a few times now. If so, it sparked the same discussion last time.
Many were imported here as new by some GMHolden dealers and I'm sure Vauxhall dealers in England etc, then converted by local engineering shops, then sold as new with a warranty.
The quality of those conversions however, was what I consider slap-dash. Some real sh!t-ugly work in order to keep the costs and time down. Mostly were 67-68 as 69 have a much harder dash/instrument carrier to convert.
Australia (and other countries of the Commonwealth) did receive full-size RHD Chevrolets and Pontiacs (exported from Canada for tax breaks -trade between two C/wealth countries) but those cars were delivered unassembled from the firewall forward. All the parts were there, but it was up to the GM dealer to have them assembled or assemble themselves.. This could have also been for tax reasons, -don't know.
The thread in my sugnature has a lot of the work that I did (see the early pages) and as Mopar said, I pretty much had to fabricate or modify every part.