Yours looks like the usual ebay fakes. Compare the guard with the ones in the picture of the Chinese troops (or,
http://mandarinmansion.com/republican-dadao ). I've seen these both in cast brass and forged iron. While these "curled tip" guards aren't the only ones used (plenty of disc guards, some S-guards, some other guards), I've never seen one like the one on your incoming dadao on a known-to-be-genuine old dadao, but have seen plenty on known fakes.
(When you get it, can you post (or PM to me) some details of the blade thickness and cross-section. Basically, how much does the blade taper in thickness, and how close to a triangular wedge is the cross-section.)