Could try Atlantis Word Processor, according to the MR Wiki it can do .doc -> ePub. It has a free trial period but isn't freeware.
http://www.atlantiswordprocessor.com/en/downloads.htm
Alternatively try poking through the rest of this list. Even if one doesn't open .doc files, maybe you can find one that will let you copy and paste the document over without losing formatting.
https://wiki.mobileread.com/wiki/EPub...ation_software