Split Word Doc into multiple html files

I've got a set of long Word documents that I need to split into multiple html pages.  The Word docs are formatted like this:

<h1>First Heading</h1>
<h2>Some Subheading</h2>
<p>bunch of paragraphs</p>
---page break---
<h1>Another Heading</h1>
<h2>Some Subheading</h2>
<p>bunch of paragraphs</p>
---page break---
<h1>Heading</h1>
<h2>Some Subheading</h2>
<p>bunch of paragraphs</p>
---page break---
and so on...

The files have to be split such that each heading and all the associated text is pasted into a new document named "heading.html"  -- in addition, it would be preferable that the html file names have no spaces.  For example, the Course Overview section would be converted into course_overview.html.  There is a page break between each section.  

I've tried multiple solutions that have been posted already, but have not been able to get them to work.  Thanks very much for helping!