A bit of an update for anyone interested. I got a response almost immeadiately from the main contact address on the Amerang website- however, they were absolutely no help whatsoever. Basically told me to 'we dont have the parts' and to 'return the kit to the supplier' which, as an Ebay purchase isnt an option. I wrote back saying that the canopy, which is the main part thats missing, is the same on all the re-boxes of the Ki61, of which there have been at least 4 that Im aware of, and that the last one is still available- just got a 'sorry- dont have them- perhaps you can get an answer from Hasegawas Japanese language website (!)' As my Japanese is a little rusty these days, I think it unlikely that is an avenue I will persue.
So there you have it. I now have 2 1/32 Ki61's with no canopies or decals......