I have a spare boot plastic if that one breaks, its all scuffed anyway so ideal to test it on lol. I don't think it's overly heavy, but my Mum couldn't lift it when it arrived in the post... 
The weight will be on the boot floor anyway, the hook will just be to stop the top flopping over the first time I turn right so wont need to take much weight.
Hadnt though of Velcro tbh, but would prefer something solid if possible.
Edit - Niall your second solution sounds good! Wonder if theres a tidier way of doing that...hmm, will think about that.
Edit again - Sod it, I'll get a Velcro strap!
Cheers guys.
The weight will be on the boot floor anyway, the hook will just be to stop the top flopping over the first time I turn right so wont need to take much weight.Hadnt though of Velcro tbh, but would prefer something solid if possible.
Edit - Niall your second solution sounds good! Wonder if theres a tidier way of doing that...hmm, will think about that.
Edit again - Sod it, I'll get a Velcro strap!
Cheers guys.