Gotcha. The formula isn't hard, density x length x pi x radius squared. That's like 650 lbs. Bet you could rig up something to get it on a trailer.
FWIW, Harbor Freight had casters on sale last week and might still. I picked up 4 like this and made a cradle to move camper shells around. They're 300 lbs capacity (optimistic IMVHO, like most HF stuff) each and 4 cost me $50. Maybe you could rig up a dolly since you'll have to move a couple of big beams around on the way back, too.