After some thinking about how to approach this, today I forged a point on the wrought iron core, and then upset the first inch and a half of the edge bars to develop a bit more mass at the tip, forged them down to points, and roughed in the curve to match the core.
I then hot fit them to the core, ground the mating surfaces clean, and wired them together. Finally, I forge welded the whole lot together. (Slideshow below.) This one fought me all the way, and while I think it's now solid, I won't know for sure until I forge in the profile and do some aggressive forging on the bias to flatten and taper it.
I also managed not to burn myself until literally the last second - putting down my tongs, I brushed the tip of the hot blade, which I'd set on the anvil after normalising, along my forearm and across an old scar...