Using XML Datasource - is this possible

Firstly, let me say I have searched the web, this forum and the tutorials etc to find something useful to point me in the right direction but had no luck thus far.

I have some XML that looks like this;

<StaffList>
    <Staff StaffId="1" Name="Fred Nerk" Mission="JMO">
        <SAC Code="001001"/>
        <SAC Code="001002"/>
        <SAC Code="001003"/>
    </Staff>
    <Staff StaffId="2" Name="John Doe" Mission="UKDEL">
        <SAC Code="001002"/>
    </Staff>
    <Staff StaffId="3" Name="Jane Citizen" Mission="UKREP">

        <SAC Code="001002"/>

    </Staff>
    <Staff StaffId="4" Name="Kim Hughes" Mission="JMO">

        <SAC Code="001002"/>

    </Staff>
</StaffList>

We have a dropdown list that contains the Name attribute of each staff element.  We have done that by using a Datasource and binding it to the XML.  Easy.

Once a Staff member is selected in the dropdown list we would like to populate a control with the value of the "Code" attribute from the child SAC Code element(s) for the selected Staff member.  We would also like to populate a control with the "Mission" attribute for the selected Staff element.

Is this possible using LC designer?  If so what tactic can we use to do it?  Any help appreciated.  Happy to reshape the XML if it makes it easier.