Went through this recently.
For a project like that - I would recommend you get them custom built mate. Its the only way you are gonna know they will fit and have the right clearances.
Anything else is gamble.
Getting custom extractors ONLY - looking upwards of $1600+, then you gotta get them coated (Jethot or other coating $400+). Adds up.
A lot of the extractors from the USA are getting welded inside the header flange. So the weld bead is on the face where the headers bolt to the heads. Lot's of peeps have issues with gaskets blowing out every 12 months or so.
So if you are buying USA made - do your research.
Varied opinions about full length v's mid-length or shorties as well.
Full length you will likely find them hanging low - which then effects options for you if you want to lower the car.
In the end, I bought some Patriot Clippster mid-length for my mild 350 to ensure proper clearances under car. Researched the crap out of it, plenty of comments saying perfect fit on same vehicle config. Even then on mine - passenger side is a bit too close for the firewall and one of my spark plug leads touches pipe on one plug. They do fit though....just not as good as I hoped.
Manufactured headers and fitment = rolling the dice. Every car is different.