Good luck trying to get a blad off the shaft unless you can find one of the old watersticks with the “hot glue gun glue”. On the newer watersticks, It’ll be very tricky to get the the blades off, as the glue is quite strong.
Another option is to order some blads from riot (they will fit watersticks) and put those on your old shaft.
NaD, do you have any extra blade? I coudl use some, cracked a blade in a hole last weekend.