Check with Metasonix themselves. I know they offer some P/S options that can handle their tube module draws, most notably across the 5V rail for the tube filaments. They're also cogniscent that the filaments draw considerably more on startup than once they're at operating temperature, since they have to overcome the thermal version of inertia in order to get up to operating temps. Once there, they draw 'less'...although, that's one massive 'less' that they draw.
Erica also has a solution to filament voltages, but I'm not sure if it's compatible with Metasonix modules...it might just be for their own tube modules. In their case, there's a retrofitted 6.3VDC supply added which supplies the filaments.
Congrats on the 0-Coast, btw...now you can see the screaming raw POWER that having full control over the patch architecture offers! To quote noted actor and weirdo John Travolta: "Ain't it cool?"