Shipping Vinyl LP's

Make sure you pack them *really* well. When my wife moved here from CA, she used USPS to ship her LPs..they never got here. She used book boxes, and media mail. The box must have disintegrated..You may want to have many small packages, no more than 6-8 inches high, with the LPs flat. USPS will give you the best rates, however, if you use media mail.

Call Amtrack. Very reliable and cheap.

I shipped 200 Lps across the country twice in the same boxes via USPS media mail and they did arrive just fine.
I used thick imported wine boxes. Hard to come by I admit.
But as long as the boxes can be dropped 3 feet and survive completely intact, you are covered. If the box is so heavy/flimsy that it cannot pass such a test, you are asking for trouble.
The Amtrack advice may be the solution... never used them, but sounds worth a shot.

I mailed a bunch of LPs USPS to Hong Kong. I went to U-Hual and got the box that is just right for albums and the next size bigger (12x12x12 and 14x14x14 I think).

Put the albums in the small box and it in the larger with wadded up newspaper between to absorb some shock. Tape well. It worked great and all 500 arrived safely in about 12 boxes.