I've been there... looked high and low... In the end I didn't go the flushed option.
Instead I went for these...
Mercator Neo & Mercator Metro
They were the best bang for buck LED batten lights I could find for my garage.
I've got no complaints. They work a treat! YMMV
I ended up buying them off ebay store. eg:
NEW Mercator NEO 45W LED Batten Slimline Ceiling OR Wall Surface Mount Light | eBay
They also offer flush style LED at considerably less than $400usd
Good luck with your search.