"I feel your pain." I have three boys, 17, 11, and 5. My two younger boys were "temporary" biters, although I cannot remember at what age exactly. Anyway, it was advised to me to pluck their cheeks. Now, some moms may be horrified by this so called violent act, but you are not hurting them nor communicating "if you hurt me, I'll hurt you." You don't do it with a lot of force. It is to shock them slightly. If your child is not responding to your saying "no" to this, he will likely not respond to that later when he goes to touch a hot stove or attempt to hurt a playmate. Desginating clear boundariers early is vitally important and this sounds like the opportunity to establish his first. As much as you enjoy nursing, as I did all three of my boys, if he continues to bite, you will simply have to give him the consequence of not having the privilege by stopping altogether. This establishes authority quickly by showing him that his hurtful behavior will not be rewarded and as much as it pains you to stop, to continue to reward this behavior will enforce his ability to manipulate you and not respect your authority later. I know that sounds harsh since he is only a baby, but they are very capable of establishing how to respond to your guilt. His getting "instant gratification" from a constant flow bottle is trivial compared to the satisfaction he'll receive by being able to hurt you while you are trying to nurse and bond (a loving time) with him. Your enjoyment of nursing him is obvious because you stated "this is really too soon for ME to stop." It may not be too soon for him if he is using this as an opportunity to control. I have watched this behavior go unchecked in friends and many of these of precious babies do go on to other destructive behavior later because it goes unchecked and unchallenged beyond a simply word they simply will not respect. And many of those parents wouldn't dream of a little pluck to show that it is simply unacceptable to hurt someone who is trying to bond and spend quality time. Even if this time is temporary, because he is teeting, if he does not willingly stop on his own because he understands it is not acceptable, the biting won't stop when the teething stops. He would very well use it as a game to see if he can get you worked up about it.
About me: I am a 41 year old mom of 3, married 22 years. My boys are the joy of my life - all different but amazing displays of uniqueness in how they celebrate life. I am always in awe.