It worked. Enough of you out there sent enough letters to Warners to convince them to release it on their exclusive Warners Archive collection which is only available to American customers on their website.
They provide a preview on their site which shows that The Big Circus is in its original widescreen format and is a decent print. To get your copy follow this link to Warners site.
As a Canadian I will have to find another way to get a copy, Ebay perhaps.
Thanks to reader Simon Howson for the heads up on this release.
Still it is finally out there in full widescreen glory.