If you sell a youtube partner channel you are essentially selling a business. A rule a lot of people have used for selling websites is to take the monthly profit and times it by ten.
I don't see why you couldn't use that here, after all if your channel is constantly making $2000 a month it should be worth a lot. So if you times that by ten $20,000 is the number you get.
Think about this in business terms. If I bought your channel, it would essentially make me back my investment in 10 months, which is not a very long time.
Depending on what niche it is in, I would contact business owners, and website owners in your niche, they are going to be the ones willing to spend that penny on a business.
Hope this helps