Actually I planned on keeping a lifetime supply of bulbs and selling the rest off on ebay or craigslist to pay for them. Then I can just pick up some used high bays and change over to 400w lights instead of what I have now, just because it would be a cool way to reduce my operating costs.
I hadn't planned on becoming an importer or whatever.
Just standard bulbs, but new in retail boxes. In volume it can be as low as $4 ea.