Seems you have a bit of a predicament.
If I were you, I would first check with a healthcare professional familiar with breastfeeding pharmacology. A lot of doctors and drug companies advise against breastfeeding when taking certain drugs without a complete understanding; they'd rather be safe than sorry.
Dr Hale is an expert - you could search his site at
http://neonatal.ttuhsc.edu/lact/medi...orumspage.html
Again, ask if you absolutely MUST give up bf to have the jabs.
Otherwise, are you sure you are willing to put yourself through this? Pumping is always hard work, not to mention boring. Sustaining milk supply is always a problem. There's always the risk that you will not be able to/not want to re-establish breastfeeding.
Is taking the baby with you not an option? That would be the easiest solution by far!!
Whatever you decide, do so as a well-informed mother and not under pressure from others.