From a premmie mum that was in your situation, with her hossie bags already packed for this baby ... here is my list:
Keep in mind that you don't need anything for the baby atm ... if you are on strict bedrest at 24 weeks, I'm so sorry to tell you but the chances are good that your baby will come a bit early and that would mean a NICU stay and there ... they got everything baby needs. So all hubby needs to get for bubba is maybe some premmie dipers .. (my hossie just charged it to my account .. so find out if you'rs will do the same) After you've been released, then you can pack the baby stuff yourself, or at least sit on the bed and deligate

For mommy:

2 pairs of PJ's (I also took a pair of yoga pants and two support tops - for when you are allowed to start walking about again)
Nightgown and slippers
Pads (maternity pad and breast pads)
Your feeding bra's and Nipple cream (even if you are expressing, they get sore and it's just much better with the feeding bra .... )
The BREASTPUMP - I got a handpump from the hossie, but had to buy the electric conversion thingy ... ask the hospital if they don't HIRE out pumps, then you can get a double pump ... much better.
Hairdryer - a girl still has to look good
Phonecharger and 2-point plug (if you need that)
Some tissues ( I cried the whole 10 days in hossie )
Socks, undies
Reading material, or your knitting, something to keep your hands and mind busy.
Sanitary products: Men usaully forget stuff like lip-ice and hairbands. Make your list for him.
My first pg ended in a c/s, so I'm not sure what you are going to need for a VB.....

PS: Ask the hospital to put you in a wheelchair and take you on a tour throught the NICU. I know we don't want to think about this, BUT it was a huge shock to me and I was not prepared for the NICU ... did not think about going to see what it looks like. Ask questions about the different machines, what you can expect if bubba comes early (baby's apperance ect). Also talk to the nurses about how the NICU work and the visiting hours and breastfeeding times. I know that here the mommies are allowed throught out the day between 6am and 10pm, but daddies have visiting hours.

I might be a doomsday preacher ... but from experiance .. it's better to prepare for the worst

Goodluck and LOADS of sticky vibes for that little one.