Dynamics CRM with Office 365 for Small Business

I'm interested in trying out the Dynamics CRM with my Office 365 Small Business subscription.  I came across an article that said to go to the portal, click on purchase on subscriptions, and then there would be a link for Dynamics under the 'Other Plans'.  When I follow those steps, the only option available under Other Plans in Office Professional Plus.  Is Dynamics not available for Office 365 Small Business customers, or am I missing a step somewhere?  Thanks in advance for your help.