From what I can tell in that letter, if they go through the LDC (RBC) they have to use those 2 different sets. If they get approval to buy locally, I guess they can buy whatever they want.
I'm curious about the actual make and models of TVs. I do some AV stuff for work and some of those larger displays CAN get expensive depending on the brand. Same with the other equipment. Without knowing that info, I can't really say if the congregations are getting hosed on those price tags.