Here's the safest and cheapest way to do it:
Postage will probably cost you around $13 to go all the way to Oregon from NJ.
Get two USPS Priority Mail boxes from the post office. This requires you to ship via USPS Priority Mail, but you get tracking and $50 insurance included. DON'T pick up the Flat Rate boxes - USPS will charge you double (they charge for each flat rate box used). You're looking for what's called a "Mailing Box" and it measures 12.125 x 2.75 x 13.375. With new USPS guidelines, I'm pretty sure you HAVE to ship Priority if you go through them. I've found that USPS is almost always less expensive than UPS/FedEx/etc.
Connect the boxes end-to-end and slide them together as close as possible. Make sure the total length is less than 30" or you'll jump up in price quickly. Tape the middle where the boxes meet and tape the ends for good measure.
I found this image on Google:
Also, this video is a little dated with regard to USPS guidelines and box cosmetics, but he still makes good points:
A note on packaging: Take your time and make sure it's secure. Nothing worse than receiving some beat-up janky box in the mail. Also, save the plastic shopping bags from Target/grocery store/wherever to use as a cheap padding material. Very lightweight and effective.