There are two types of round sprung-buffers with riveted bufferplates (genietet) - as you see as well from the pics of the prototype:
1. Federpuffer Bauart Siegen, Art.Nr.: Günter Weimann FP 1. This constructed in 1924, it has a buffer-length: 650mm. It's constructed by UIC, as UIC started 2 years agon at 1922. price: 22,50€.
http://www.wagenwerk.de/h0de/fahrzeugba ... gen-1.html
2. UIC-Hülsenpuffer 620, Form C, Art.Nr.: Günter Weimann FP 16. This constructed by UIC, and it has the standard buffer-lenght: 620mm. Most of the european freight wagons, as well the locomotives, either electric, or diesel, have this length. I suppose that this locomotive, as it's constructed in the 1950s, even though it came to SEK between 1962-66, it has this type. price: 22,50€.
http://www.wagenwerk.de/h0de/fahrzeugba ... m-c-1.html
However, I'll go again in Rentis (if I found there this loco) and take a count to the bufferplate, which from upgrading experience of buffers, it has definetely a radius of 450mm (5,2mm in HO), as well as the buffer-length to be sure exactly, which is the right one, either the 650mm, or the 620mm.
Thanx
Dimitri
So that I may buy it. 
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