Help on Awning size

Help please as I feel we are swimming in Custard!!! We have an Elddis 205 that is purfect for our needs but am finding the awning a job to fit for my wife and I, basically its heavy and need more hands than we have. We still want a full awning but a lightweight model. My confusion is that the size we have is a 7550mm. can anyone advise what size of a  lightweight  one we need as they all have more than one measurement!