My jointer is a Powermatic and I recall it weighs at least 500 lbs. I think the Delta is just a little lighter, but not by much. Buy a couple of sheets of half inch 4x8 they use for roofing. Cheap as heck. Lay one out across the gravel, roll to the end, put the second sheet next to it and roll to the end of that. Just keep switching them out til you arrive. Might be cheaper than new, oversized casters. Hire a couple of beefy guys, or fill a cooler with beer and find some friends our your kids to help you with it. The only difficult part is getting past stairs or split levels.