Talk to John over at Antek - he makes some great toroidal transformers for SS and tube projects. He can recommend one for you given your B+ and filament VI requirements. I bought a 1T200 for my Aikido 9-pin project - it is damn near as big as my 400VA transformer for my F3 project. Plenty of juice, very nicely made and only $ 39.00 INCLUDING S&H.