Yes, as mentioned, spadroon blades persist into the 20th century.
The example I mentioned from Lion Gate is gone but there is a fresher example there. Look at the Late 19th Century Prussian Civil Service Sword listed at
http://www.antiqueswords.com/categor...ed-Weapons.htm and note the same type of blade certainly used that late.
As to the Scandinavian types of slim infantry swords with double guards and also the German degen of the 18th century, you are going to see more with double edge blades not unlike the British 1796 heavy cavalry dress swords. There have been some of the earlier German swords circulating on Ebay lately.
The folding guard example at Old Swords lacks good blade pictures but certainly the same spadroon blade.
Cheers
GC