Impa's Scorching Naginata - Hyrule Warriors

[sniperi]

I usually just try to figure things out for myself, but this is my first time making something like this and I'm way out of my element, so any suggestions are appreciated! I'm wanting to make Impa's Scorching Naginata, from Hyrule Warriors.

Reference images I'm using:
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I'm fairly certain I've got the blade down, so my current issue is making the decorative gold bit that starts at the bottom of the blade. I was thinking I could make it out of worbla, but the moment I sat down to actually do it, I had no idea how to go about making a shape like that. x_x For the rounded part in the center, I'm going to try using a big christmas ornament, so I figured the worbla would wrap around that easily. But the upper bit that fans out is killing me, I'm not sure where to start. Like I said, any suggestions at all are super appreciated!