As
@Erel suggested, you can set a map where the key is the label you pass to the standard ComboBox and the value is anything you want to associate with it.
Another approach is to design your own ComboBox class (CustomView). I did something similar in order to "hide" the need for an external (to the class) map.
In my case the "trick" was to set a new internal type and the corresponding internal list:
Type dgCB_Item (cLabel As String, cValue As Object)
Private dgItems As List
Clearly "cLabel" is used for the standard Combobox/Spinner while cValue could be anything.