Applying Master Pages

I am using InDesign CS6 to produce a 92+ page catalogue for an annual photographic exhiibition. I have created a number of spreads (23) for this with left and right hand headers. However, our printer requires the pdf we produce to be in single pages and I am finding it impossible to allocate the correct handed version to each page. Is there a way that this can be done? Obviously. I don't know what hand the pages are going to be until the whole catalogue is completed and the pages are in order. Any help would be appreciated.