Actually, thats a pretty neat job compaired to some I've seen. There used to be fibre glass ones for sale, but I found these were a very poor fit and needed much 'adjustment.' There were some tin patern ones knocking around a while ago on the bay, and I managed to get some of these for fitting to my droop come the time... However, I have before made some thin 1.5mm to 2mm lead flashing which can be moulded pretty much to any shape required, screwed in with washers, and the folded edges then gooped with a suitable sealant to make the inner arch as good as water tight to protect the A pillars.
Just some alternatives.
Dan