Did you buy this from the previuos owner, or from a dealer?
If from a dealer, it is possible the previous owner still has the book, but failed to take it when they did the changeover to their new car. Dealer then can't be bothered to chase, or owner doesn't care to make another trip to the dealer. Happens with spare keys frequently.
You could try contacting the previous owner. If they're not local, send them a postage paid padded envelope with your address on it, so it is simple for them to send the book to you. Worst case scenario, you lose the cost of an envelope and stamp.
All you need now is for someone to weigh their handbook for you.
Or, trawl eBay for 'breaking' similar models. There may well be a few handbooks there about to be binned. Find one as close in age to yours as possible.