Nnjlon, there's something I'm picking up on in your posts that no one here has mentioned yet. It sounds like you really don't want to be giving your boyfriend oral sex. If that's rooted in not recieving pleasure in return, or his selfishness, that's part of the issue - but if you don't want to be having a sex act? Don't. It doesn't matter if you've been in a relationship for a long time, and are usually sexually active -- if you don't want to be doing it, you shouldn't be doing it.
His cavelier attitude in telling you to "take one for the team" shows a lot of disrespect to you and your feeling about this matter. Rather than playing games by witholding oral sex or tempting him with other sexual games, why not tell him, flat out, that you aren't enjoying performing oral sex on him? And remember, also, that you shouldn't be performing oral sex on him so that you can get it in return. Do it because you want to - no other reason really cuts it.