First of all welcome to Cosplay Island! I hope you enjoy your time here.
Your second link above doesn't appear to work but I found this image
my suggestion would be initially to find a long wooden broom handle or something along that lines, you can get that kind of thing from the likes of B&Q or Homebase. This will give you your base pole.
The bit at the bottom where it flairs out, you could get sheets of some kind of thick foam,
plastazote or craftfoam (EVA) and glue the sheets together until it is roughly the thickness of your pole. Cut out the 4 pointy shapes and then glue them to your pole at right angles to each other. As an alternative to plastazote or craftfoam people seem to swear by yoga/camping mats which you can pick up from probably camping shops, pound shops, big Tescos etc.
You can also use foam/camping mats to make the blade. Just cut out the outline of the blades with a sharp knife then hold the knife at an angle to cut the 3d-ness into it. I find
these kinds of knives the best.
The detailing around the blade and the top of the pole you could probably just make out of clay. Shaping it around the pole and then once it's dry/hard pull it off, stick some glue on the pole and glue it back on. Failing that, nip to a place that does curtain poles and you can get ends for them to make them look nice, one of those might be suitable if you can find one the right shape and size.
The bit at the bottom where it's tapered might be tricky unless you have a look around the likes of B&Q for something that's the right shape. You want it to be sturdy as well as you'll be resting that bit on the floor a lot and if it's not sturdy it'll get mashed.
Hope that all makes sense, if it doesn't don't worry about asking and I'll try and explain it better, it's a bit late now so i'm probably just rambling
