There are a few ways of achieving this, with varying degrees of ease of reuse. You can have a DataTemplateSelector that could return the appropriate DataTemplate for a given property (depending on how this is written, you may be able to use it for each of your properties).
You could create a DataTemplate for each property, and change visibility based on a DataTrigger (this gets really annoying, as it is a lot of copy and paste).
I think the easiest way of doing this is with a specialized ControlTemplate for the TextBox. Basically, when it is disabled, instead of graying it out, you can just make it look like a TextBlock:
<ControlTemplate x:Key="PermissionedTextBox" TargetType="{x:Type TextBox}">
<Border x:Name="bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}">
<ScrollViewer x:Name="PART_ContentHost" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="bd" Property="BorderBrush" Value="{x:Null}" />
<Setter TargetName="bd" Property="Background" Value="{x:Null}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
Then you can use it like so:
<TextBox Text="{Binding PermissionedText}" IsEnabled="{Binding CanEdit}" />