Another point of caution...
I went the same way and was warned that the colour of later SD is different from the wartime SD.
This apparently changed somewhere in de late 50's (correct me if I'm wrong).
On it's own it's not very noticable, but when in company of some wartime SD, you'll stick out like a sore thumb
Or so I'm told...
I bought an early 50's (I think) SD which is virtually identical in colour to the wartime SD I have. I still have to add the fourth (fifth) button.
Also, wartime SD (or early wartime SD) had the belt sewn to the tunic at the rear. Later SD have a seperate belt.