@GuacamoleSalad, I had forgotten about this company because it's been a long time since I've ordered from them, but you might want to try searching at Save On Scents. They have a billion (almost!) different types of fragrances of all kinds, including odd ones.
Also, they have a "sniffie sample" set for $6.99 (including postage, I think) where you can order five tiny, 1.2ml sample bottles - enough to do cotton puff tests/blends but not soap - of their fragrances. They don't have a Blacksmith FO, but maybe you could combine other ones, like Campfire, Smoke, Metallic Steel, Coal/Tar, Lump of Tar, Gunpowder - those are some of the ones I found with a relatively quick search. Here's a link to the sniffie option:
https://www.saveonscents.com/product_info.php?products_id=4802
I don't know how those scents would hold up in CP. Many of them have reviews, you could see if any mention that.
ETA: It just occurred that this might not be worth it unless he is a very good friend indeed, or was willing to underwrite the costs. In any scenario with a scent like this you'd probably have to purchase a bunch of different FO samples for sniffies, and then enough of the final contenders to do small sample CP batches. It would end up being a pretty expensive experiment that might not work in the end anyway either because the scent doesn't stick or because the recipient says something like "it's not quite right, maybe it needs a soupcon of ___". Which for me, after all that work, might end in a dead-friend-scenario
If you've found the seller it might make more sense to just buy your friend a couple of bars.