Where can I find an adapter that holds 5 headphones and plugs into my TV?

Answer 1

You might have to make one. I haven't seen such a thing. I sell two way adapters, but I think a 5 way might have some rather serious loss issues due to impedance mismatch.

Answer 2

Try 8th Street Music. I have always had good service from them. If you do a search on headphone amplifiers and then call their customer service number, they can tell you if there are cables that would connect to the TV.

PS if you can make do with 4, the amps are a lot cheaper!