Start the bottle TODAY, and use it once a day. Any bottle should be fine. From the Walmart cheapies to life factory glass.
1 ounce per hour. So have your SO give baby 2 ounces and then no breast for 1.5 hours (if possible)
For some babies there is a window of bottle acceptance. And your window is now.
BFing, CDing, all natural mama to three boys! Certified lactation Counselor