If you do a search on eBay UK for RDX bonnet, a company called bolt on bits has a listing. But they won't ship outside UK. Hood to the UK folks is soft top to the US.
Bolt On Bits
Phone : 01274 688388
Email : email@example.com
A friend of mine runs a land rover / range rover specialty repair shop. Based on his experience, they are capable of stopping anywhere, anytime, at any cost.
I don't know about the brakes, only their unreliability.