The main thing with importing is being able to get through customs. Remember that the container will likely have to switch drivers. Also, I suspect that the amount you are looking to bring over may be on the small side. A 40' container of bananas has about 40,000 lbs and this generally is the smallest amount that gets shipped. You could try to get in touch with a tomato shipper and gets some shipped in that way. If you have been shipping to Japan you should be aware of the kinds of paperwork necessary.
In Florida, the main organic broker we have is:
Organic Produce Distributor Buying Club Coop of Organic Fruits & Vegetables