What suggestions does the seller have ? If it were me - I'd try this mob;
http://www.packsend.com.au/packandsend_int_freight.phpThey actually have a box which is the correct dimensions for a playfield. They fill the box up with foam and drop the playfield in, then do the same for the top. It is a "Custom fit". I'm not sure if they have an office in the USA. They are cheaper than UPS.
