Well if you are using Word 2013 and all of your users are using Word 2007 or higher then content controls (vice document variables) would, I think, be a better choice for data targets in the document.
What you need is a three column listbox contol. Put the sales rep name in column 1 (0 in control speak), the phone number in column 2 (1) and the email in column 2 (1). You can hide the contents of columns 2 and 3 (1 and 2) and only show the sales rep name in the listbox. When the user makes a selection and clicks ok then you populate the variables or content controls with the listbox column values.
Lots of methods and techniques here:
http://gregmaxey.com/word_tip_pages/..._combobox.html