We have bought a Bessacarr cameo 550 caravan and are currently looking at purchasing a awning. I have found a bargain bradcot one which is a 960 however upon checking the bradcot awning guide it states I need a 1005 sized awning.
If the secondhand one is cheap enough to make it cost effective, it is possible to get the length extended by the extra 45cm you require at any good tent and awning repair shop, they just insert a V of new fabric into the roof of the awning, and replace the attached awning bead with a longer one.
Julia
------------- Just love to be out amoungst Nature and Wildlife
Celebrating 37 years of Caravanning in 2019, Recently Considered Retiring, but Totally Addicted for Life!
I agree with 'andycapp' as the difference in length is 45 cms. which in imperial measurement is 18 inches. This would mean that it would be 9 inches too short at each end so no good for your caravan awning size unfortunately therefore I would go with the advice that 'romany girl' has suggested.