I forgot to say 4x5 and 8x10 is okay but there is many actors selling this size of film so all of them make money but not gettin fat!. The 11x14 cameras is not that usual out there and in that size the competition is still hard. After that the market is so narrow that no one can grow that big so they can run an entire production of coating and with own recipe itís got to be stopped time to time. To start again itís possible with hard work and as I sad before with lots of losses. The rest of it you probobly manage to put it together too.
I beleive that is one of the reason that no existing companies cutting film to those sizes at all time. thats why they taking orders and they cut after that or maybe a little bit more. Observe that cameras over 11x14 comes a variety of different sizes, proboly the 7x17 is the most common.