Great to see Katzbalgers available separately. Though whilst they were still prevalent in the Plunderhosen period rapier type swords also start to creep in which could be nice for a bit of variety. I think TAG already offer those too.
Katzbalgers;
This one?
http://www.theassaultgroup.co.uk/product/sheathed-16th-century-sword-x-10/
Rapier type swords go back to the 1400s and sword quillons with fancy guards possibly around the same time, in response to wielding swords in a certain manner...

Notice the position of the index finger of the guy making a thrust in the center and the one in the upper left...
If you can, find a copy of
Art, Arms and Armour: an International Anthology, VOL.1, 1979-1980, for Ada Bruhn Hoffmeyer's article,
From Medieval Sword to Renaissance Rapier: covers not only the changes, but the various national styles of rapier blades and guards.
Just noticed that TAG are now offering Katzbalgers:
http://www.theassaultgroup.co.uk/product/katzbalger-sword/...

Looks to be sheathed, though would like to know its length...