Moving arcade machines to and fro the country, I use NAVL (North American Van Lines) and I'd say on average, a 400 pound machine costs about $350-$400 to ship. After you send one machine, they typically will do a half price deal on the second. And we're talking about them handling this antique/collectible stuff with kid gloves! Blankets, shrinkwrap, etc. Never, ever had a complaint from them. They would LOVE to move something already bundled up on a pallet I bet. Be a lot easier on their end anyway. Just remind them to bring a pallet jack!
In the future, I'd recommend looking into NAVL (Michelle Bianchi) to be precise, if you're getting $1k quotes from UPS Freight. She's the lady you'd want to get ahold of for this kind of move and a sweetheart that doesn't "overcharge".
Terminal to Terminal via Forward Air (the drop off and you pick up at the airport) would have been even cheaper. $250-$300 average if it's already on a pallet...