Rodd,
I just looked at my Force 10 Bar-B-Q (an old kettle type) so I am coming from the background of, --- it looks like the orifice looks like it screws into the regulator and fits into the feed pipe with air vents and a shield around it.
Have you considered going to Good-Will or some place like that and pick up an older unit with about the same size burners, gut the part you need and rig it to fit your unit?
As long as you are careful to make sure you have NO leaks around it, it might work. After all, it's only a small brass fitting with a very small hole in it.
I know when we were in Mexico, every one uses propane to cook with and parts were VERY low cost! So we picked up spares there.
Greg