I was hoping to do the same at a similar Jubilee function I held last month. Unfortunately, the Dept. of Canadian Heritage said that the large cloth flag will not be available for distribution to the public, as it was in 2002 for Her Majesty's Golden Jubilee.
I can only surmise that the potential cost played a role in such a decision. However, the Dept. will provide you with the dimensions and specifics of the flag should you wish to have an outside source make it for you.
Good luck and God Save the Queen!