Bowing The Marimba

Can anyone tell me, approximately, the kind of sustain (lengthwise) one gets from bowing the marimba in a low range (D below middle C), once the bow is lifted?

Very little, very thin. Marimbas don't bow very well.

Unless you use electronics (amplification—bowed marimba would be very quiet—plus some kind of tape delay/reverb) you'd probably get more resonance from hitting it with a mallet the normal way.