It may disappoint some readers, but I'm afraid there are very few usual or rare types of armor on this list. I wouldn't have any use for them (since they would provide the same armor classes as the traditional armors from the original books) unless the party ventured into parts of the world where metal and leather were very rare, or useless due to the environment. At some point I might calculate how to make armor out of rattan or thatch, if the matter came up. It hasn't yet.
The daraq on the list is formed of turtle shell, and is included because the hardness is virtually equal to a wooden, metal-reinforced shield. Druids traditionally can only use wooden shields, and therefore are exempted from the metal ... it seemed reasonable to me when it was argued that a druid could fairly use a turtle-shell shield. Although not wooden, it is 'natural.' It's fairly rare, but apparently the armorer has some in stock.
The location for these tables, incidentally, are modern day Brasov in east Transylvania - in 1650, called 'Kronstadt.' The main routes into Kronstadt are over the Carpathian mountains, where the majority of goods are shipped into the Danube delta to Qalat (modern Galati), then overland. From Germany, goods come down the Danube and are transhipped from Turnu Severin to Krajova, and then into the south of Transylvania through Herrmannstadt (modern Sibiu). From the north, including Poland and the Baltic Sea, goods tend to follow the routes from either Gdansk through the Carpathians and into Klausenburg (modern Cluj) or from Stettin (modern Szczecin) through Dresden, Prague, Miskolc and then again, through Klausenburg. Kronstadt is a bit of a backwater, so the faster routes tend to flow north or south around the Carpathians through other more active trade cities. Kronstadt is an important collection point, however, for Transylvanian goods to be shipped to the Ottoman Empire, and there's a good bit of smuggling that goes on through the lesser used, higher mountain passes.
As if the reader needed to know any of that.
No doubt it will be seen that the prices are very high. That's because if the table is going to charge a couple of gold pieces for something like a fishhook, that weighs a tenth of an ounce and requires some trouble to make is going to cost a mere 7 c.p., then something that is 6,400 times the weight of a fishhook, and a bit more trouble to make, will cost upwards of 300 g.p. That's just the way it is. One problem with randomly pulling numbers out of one's hat for an equipment table is that it rarely accounts realistically for all the various features that fit into a particular object. For example, merely to poke a number of gold at "splint mail" as a measure against its armor class value hardly takes into account the difficulties of creating the joints between the chain links and the splints ... which are a great deal of trouble. It's useful if some sort of logic can be applied.
Point in fact, the mithril armors listed here are NOT magic. They are, however, highly durable, and very likely to survive a dragon breath or similar attack which would burn away lesser armor. The mithril isn't pure, not by any account - it is an alloy, of course.
The skullcap was included for magic users. I have a rule that says when a natural 20 is rolled, double damage occurs. Moreover, the d20 is rolled again, and if either a 19 or a 20 comes up as a subsequent result, the damage is tripled. However, if the second roll is a 19, and if the individual is wearing a helmet (or a skullcap), the damage is NOT tripled, it is only doubled. By including the skullcap on the equipment list, expensive as it is, I made my mages happy.
Regarding the chausses and the hauberk. I use these names to describe the linen underclothes that must be worn beneath metal armor. It is a bit of extra expense, a bit of extra weight to the whole character, and in general something people tend to forget to buy. I usually remind them, but if someone who has been playing for a long time and fails to remember, I'm not above telling them they can't use their armor for awhile. It encourages players to think deeper than the usual books ... and it is like catching players who forget at the start to buy boots. I don't know if others have that problem, or if they forgive players and let them buy retroactively. I'm not always so kind.
Enough for now. I am always open to good-spirited questions.