Weird timing, but I got a reply from Brion at Amp yesterday; A lot of the stock was trashed or put in for recycling, but he's managed to save some bits. He's still got some stock and is willing to help us out.
Sad times for us retroheads, but above all, mucho respect to Brion. Top bloke, and PHENOMENAL customer service - They haven't made bike parts for around 15 years!