Now, I'm not sure if you can actually buy them but you can surely rent them. A lot of prop rental houses have louver fluorescent lights for rent. I suppose if you can, you could probably convince them to sell them to you. Now they might have been retrofitted but I suppose the parts needed to convert them back (ballasts, lampholders, etc) can be had on eBay easier than a fixture. In case you're wondering where a modern film/TV show with louvered fixtures in the set got them from, they probably got them from these places.
Some styles I recognize include: Day-Brite Lennox-4, Day-Brite Viz-Aid-2, Lithonia Chief-Lite, Amalgamated Luvex, etc
http://inlightdesigns.ca/product-category/fluorescents/http://www.practicalprops.com/rentals/fluorescents.htmlhttps://ecprops.com/products/lighting/fluorescent_2_foot/2_ft_fluor.htmlhttps://ecprops.com/products/lighting/fluorescent_4_foot/4_ft_fluor.htmlhttps://ecprops.com/products/lighting/fluorescent_8_foot/8_ft_fluor.htmlhttps://www.rcvintage.com/?name=LIGHTING-HANGING-LAMPS-FLUORESCENTS&Scategory=LIGHTING+%3E+HANGING+LAMPS+-+FLUORESCENTShttps://cityknickerbocker.com/collection/fluorescents?toggled=1&filter_style=9Full disclaimer, I'm not sure if these companies will sell/rent to individuals. I suppose you could try contacting them if you want to buy one of those lights. If not I suppose the pictures are some good eye candy. They also tend to be located in cities that have a local film industry (Los Angeles, Vancouver, Toronto etc)
