A left-handed rifle - good one!
How about something less complicated, like a little spacer to lengthen the butt or a Short stock? Yes both of these existed for the C7 and C7A1, but no one ever saw them. A decade and a half ago on the old Canadian Firearms Digest (heh? who remembers that?), there was one loudmouth who went on and on about his Bosnia service and how it qualified him as an expert commentator on almost all matters service rifle. He had other opinions too which are off topic. One thing that I do remember was how he fought with his Company Quartermaster, which is never a good idea, to get an issue of Short butts for his section. The theory being, with body armour on the regular length butt is too long for proper sight acquisition.
I've fired several good walk-up annual qualifications with C7A1 by selecting a Short butt rifle, on the principle that it was set up and held aside for short statured shooters, and would be uncomfortable for a normal sized shooter, therefore having less barrel wear. I have neither short or normal length arms, but a tolerance for recoil and positioning.
The other little advantage is a 1/2" spacer for the buttplate that makes the rifle just a little longer. This really helps when doing rifle drill and your fingers barely touch the front sight guard. It is never comfortable doing drill slightly twisted over to one side.