Craig,
WHOA!!! THAT's a cool truck!
COE from '41 - '47. Possibly a War baby, though it's hard to know for sure. That's a Champion Pump on the front bumper, runs off the front of the crank shaft. Probably around 400 gallons-per-minute. Champion pumps, I think, were sold by a company called Darley, a catalog-supplier of fire equipment and trucks for many years (see eDarley.com). They were fairly wide-spread in the war, and popular with commercial-chassis fire engine manufacturers selling to smaller and rural departments.
The large black hose in the bed is a Hard Suction Hose, used for drafting from lakes and such. The truck would have carried two of those at least, prob. on the driver's side. The brackets on the pass. side held a ladder. The hose reel on top is called a Booster reel, used for smaller fires and wild fires.
As for worth, among fire-truck nuts (like myself!

)the COEs are worth a little more, due to how rare they are. And being a '40s vintage also spells somewhat rare. On the down-side, fire truck snobs don't care about commercial chassis trucks, instead valuing the Seagrave/American LaFrance/Mack custom fire apparatus a little more.
You say 4-wheel drive - how do you know? That would REALLY be rare. I'd say Virginia isn't too far off the mark. Offer $1500 and see what they say. I paid $2300 for my '41 conventional with a front-mount pump, here in St. Louis. My friends said they'd never have paid that, BUT, I have NEVER regretted it. Pure smiles! (BTW, just returned from a 450-mile trip to Indianapolis in said truck - more on THAT later!)
By-the-way, there IS a fire-engine forum here on the stovebolt, it's called "stovebolt volunteer fire department, and it's a sub-heading of the BIG BOLTS forum. The guys are all terrific, and if you end up with the truck, I can assure you a prime spot in next-year's "Firebolt Calendar"!
-Michael