Which model? Blumblys or the original post by Nathan? Depends how far you want to break it down John? Magister or not they are still both SB35 model 201s. The previous posts have all the info you require. Turn the image around on Nathans posting and youd get a more accurate idea,But Only the serial number will tell you for certain what sub series/year it is.
Nathans model Unknown SB 35 201 Possibly series 1....Blumblys SB 35 201 series 2 or 3.