You have one helluva channel that's doing well you should just go on ahead and monetize that one either with AdSense or a MCN network. If it's not a copyrighted channel then go with AdSense if there is copyright content on there go with a MCN.
If you desperately need the cash right now and want to sell it then sell it for no less than $3,000. Your channel is worth a lot of money but it might be worth more than $3,000 but maybe you can meet it with someone in the middle and sell it for $1,500 to $3,000. If they won't pay that amount then keep it for yourself and start monetizing it immediately.