That's about the best look you will get without resorting to color compensating filters. I would guess a 10cc blue should give you the effect you are looking for using the tungsten film.

"I always wondered why tungsten film was rated at iso64"

I'ts not necessarily. Kodak makes both an ISO 160 and 320 tungsten balanced transparency film.

My advice is to use the filter with a high ISO speed film to get the results you want.