As noted above, you should see if you can buy a box from Parasound.
Another option is to contact a packing company like the Box Stop. You should ask the Box Stop (or other similar company in your area) for their opinion on the best way to pack and ship your unit. This will ensure your amplifier gets packed correctly. For example, see http://boxstop.biz/
I have used them several times and they are very good. Most likely, they will use a double box, include bubble wrap and/or foam, as needed, to protect your amplifier. The use of a professional packing company will help ensure your amplifier get delivered safely. The cost for this professional packing is reasonable and is recommended because of units weight.
Another option is to contact a packing company like the Box Stop. You should ask the Box Stop (or other similar company in your area) for their opinion on the best way to pack and ship your unit. This will ensure your amplifier gets packed correctly. For example, see http://boxstop.biz/
I have used them several times and they are very good. Most likely, they will use a double box, include bubble wrap and/or foam, as needed, to protect your amplifier. The use of a professional packing company will help ensure your amplifier get delivered safely. The cost for this professional packing is reasonable and is recommended because of units weight.