Below pictures supplied by Dave
The first two photos attached are what Dave has taken today, the first being the original photo, and the second is one he's cropped and skewed to try to match the view in the postcard.
The third attachment is the view from Google Streetview of the spot from which Dave took the photo, and the fourth one is from Google Earth showing Mottram Old Road from the viewpoint up to the buildings shown.
Dave thinks the actual viewpoint for the postcard was down the slope to maybe level with where you can see the horse in the top to pictures, as the hills in the background on the postcard look a bit lower down than in his photo (you can just see the distant hills faintly on the postcard).
Thank you Dave for a great update