[Arran]

Mike;
I'm not saying that you can't use them, or that they won't work, but why be cheaper and use 1 amp diodes when 3 amp ones are still cheap? Don't forget that the heaters will draw more current the .3 amps whilst the set is warming up as well, it still won't hit 1 amp but when you are only talking about pocket change to use heavier duty diodes why not use them? But just to make sure it would not hurt to use two in series, regardless of type. The main advantage in using a 1 amp diode over a 3 amp is if you are producing a product in the 1000s where nickels and pennies add up to many dollars. However a single tube from an early AC/DC set still costs many times more then either type of diode.
I still would prefer a capacitive dropper of course, which costs more then diodes and resistors of any current rating, but the no heat and soft start aspects more then outweigh the costs. As I said, if you get the type that fail as an open circuit, I think Panasonic makes one such type, then that eliminates the possibility of the cap shorting out and blowing up your tubes.
Regards
Arran