I believe TV/0287 uses UEI protocol 0068, which hasn't gotten much attention from the JP1 group. It might not be used at all in the US.

I can tell you that there are only 64 possible commands, but they don't have contiguous EFC numbers. They are scattered 4 times each through the range 000 to 255 (and 4 more times in 256 to 511, etc. but you can ignore those).

For example, you found EFC 181. You may notice that 165, 173, and 189 all do the same thing as 181. There are lists of the 64 EFC numbers that have unique meanings in this type of protocol, but I forget where and it might be just as hard to test 64 from a list as to test 255 without looking at a list.