Office Licensing for WMS 2012

Hello,

I am looking to setup a WMS 2012 (Standard) for a small business client (5 total users at this time).  I want to install Office on the server.   Do I need to buy Office through the Open License program or can I buy retail licenses for each user?  The client doesn't need most of the applications in Office 2013 Standard...they really only need Word for the most part which I see is available but Word through the Open License program is more expensive than Office Home and Business retail. 

Would using an Office 365 subscription be an option on WMS 2012?

Thanks,
Chris

Chris