You can definitely apply to bring your family with you; however, you will be the sponsor for your family members, at least that is what I would believe after looking over the VAF3 form. There is a place for you to give additional information to be considered.
I couldn't find a specific amount that would be needed to satisfy immigration. You probably should contact the embassy to see if your sponsor's finances can be considered. Also, if you are given permission to remain for 12 months, your spouse can be given permission to work in the UK, though I don't believe you can claim this as support.
Here is a site you can go through that might help you:
http://www.ukvisas.gov.uk/en/howtoapply ... udents#Q15.
Maybe someone else will have more info for you.
Good luck. Cheers!