You do NOT need need a mold, you need a template!
I would get yourself a small piece of 1/4" or 1/2" MDF and scribe or trace the pattern. Rough cut with a jigsaw, bandsaw, or whatever close to the line. Use a pattern makers rasp and file it to a perfect fit.
You might consider doing steps 9 and 10 prior to steps 7 and 8Here’s what i’m going to do. I have some 5-6 mm ply going to cut 3 templates at the rivets. That’s an easy place to align to all during the process.
View attachment 445178
1 remove the existing wood
2 cut rectangular and flat blanks. Might use a piece of cherry i have.
3 cut the end bevels, get the blanks to fit well
4 mark and drill the rivet holes by holding one blank in place at a time, mark the locations from the back side, drill clearance holes on the drill press
5 secure the blanks in place with a couple of spots of epoxy. Not a full coverage smear
6 shape to fit the templates,
7 countersink the holes, install rivets
8 add a coat of blo
9 straighten the blade, grind the tip
10 clean up & polish the metal
11 post pictures here.