Sorry, posted wrong brand in the posting title. They are Schneider True Cut 750 IR's.
Details here at Filmtools:
4x5.65 Schneider IR for $280
http://www.filmtools.com/schneider-optics-4x5-60-true-cut-750-ir-filter-68-121056.html
Also have a 6x6 available - $400...
Might be a dumb question but i've never lit for greenscreen. I've got a 12x greenscreen about 12 feet outside of a window that needs to be keyed out in post. Question is can I light the green with daylight lamps and light my interior to tungsten without it looking drastically mixed? All that...