You mention 'vacuum bag', can those storage bags be used for this?

Good question, I haven't tried doing it either way or arything like it.

The bag is probably flexible enough and strong enough to get good
clamping pressure with cauls.

I am not so sure about using a domestic vac to create and maintain the
pressure. You can't solve the problem of air leaking back into the bag
by having a domestic vaccum pumping continuously, well you could but I
don't think the motor would last very long.

I did a google but couldn't see any comments.