Curved or straight? I'm at work and will be for the next month, so I can't measure my straight one, unfortunately.
Do you need to know for pouches? I have Canadian Pattern 82 pouches for them (they work with the straight ones; I think only British were curved) and interestingly they are also the perfect length for Glock 33-round 9mm mags, which might help give you an indication of the overall length, as they were within a fraction of an inch from one another. I think Israeli and South African pouches exist for them as well. I've seen Belgian-purchased FALOs in use with them in photos from the 1960s, so perhaps they also made pouches for them at some point (never seen them, though).