You should be able to wrap a couple of those axles up with cardboard and tape them well with strapping tape, and send them FedEx Ground or UPS Ground.
Both carriers will take odd shaped stuff like this as long as it's in cardboard, up to about 125 pounds in weight. I'd think you can tie 2 or 3 together and wrap in the cardboard and strapping tape and they'd be fine. Might puncture a few Xmas gifts but they certainly are shippable. I sent off a big heavy dog crate to MT from NH and it was about $45 in cost, box was 45 inches long and weighed about 48 pounds with $400 insurance….
That's a great deal for axles for sure!