I think defintitely don't wean to a bottle - it is really not necessary & is too closely linked to the breast in its delivery for the child to not want boob instead. This is esp so if you give the milk as a cue that it is sleep time. My first never had a bottle & self weaned at 16 months after I intro'd the sippy cup of warm at lunch time (He was used to the sippy cup already as it was what he drank juice/water from). I will do the same with number 2 when the time comes.
The other thing is why not just sub with water or watered down juice & give it with lunch? As long as your child is getting enough calcium from his/her diet & little drinks of milk throughout the day for thirst, then the missing lunch time milk won't be a problem.
Otherwise all I can offer is this - you have to stand firm if this is what you really want to do. If you are caving in at the crying (I know they can be VERY persistent) even a little bit, the message will be that if he/she pushes hard enough you will give what they want. Having someone else help you deliver the message helps too - ie: hubby on the weekend - that is how I dropped the breakfast feed (hubby got bubs up and went straight to breaky while I slept in!!!! Heaven!)