To buy things takes time (a week) and effort, mainly a Streetwise skill roll vs 4, but you can also use a Craft skill to locate materials relevant to your craft. You can use Common Knowledge for Common materials.
All items will be rated as follows:
Common 0 1d6+1 allotments
Uncommon +2 1d3+1 allotments
Rare +4 1 allotment
Very Rare +8 1 allotment
A magical item +2 extra 1 allotment
So each week anyone with Streetwise may search for one type of item (common, uncommon etc). They should have a list of items ahead of time to match the possible number that can be generated. Multiples of the same item are possible.
Multiple people can co-operate to achieve a result.
Some places may be better than others when it comes to finding stuff. The city of Tyre is a major mercantile hub for the entire region and GMs may allow +2 to the above finding roll in such a city. On the contrary, some cities are remote or poor and may suffer a negative, such as Thebes due to the political situation there.
Bronze is actually not that bad a metal to use, it is only when you start making steel that it falls behind. Raw iron is actually worse than bronze and it wasn’t until iron was improved into steel that it became useful. Never the less I am assuming for this game that Iron is poor steel, and Steel is better steel, and that both of them are better than bronze.
Iron weapons +1 Armour Piercing (AP).
Iron armour and shields gain +1 armour value.
Iron is rare.
Steel weapons give +2 AP, and ¾ wt (not cumulative).
Steel armour and shields gain +2 armour value and 75% wt.
Steel is very rare.
Magical enchantments can add to an existing weapon +1 or +2 to hit and +1 or +2 damage, and variable wt mod (none of which are cumulative with iron or steel, take the best).
The cost of Iron items will generally be x4, of Steel items x8.
Note that some arms and armour is not available in ancient times, partly because bronze wasn’t a strong enough metal to make them viable, and also because the technology just didn’t exist yet.
I have also altered some of the stats to reflect more closely the period and how the weapons were used.
These items are an abstraction of trading goods, representing a bundle of different items of saleable quality. The rarity and cost reflects the quality and desirability of the items. In general more expensive items are smaller (gems, jewels, spices etc).
Merchants sell these items in minimum quantities, as a package.
Iron armour has +1 Armour Value. Steel armour has +2 Armour value and 75% weight. This bonus does NOT stack with magic. The cost of Iron is x4, of Steel x8.
*Sling bullets are made of cheap metals (lead or bronze) and shaped, wt of 2oz (8 to a lb), cost $4 for 8.
Iron axes, arrows, javelins and spears gain +1AP. Steel axes, arrows, javelins and spears gain +2 AP. Knives are too light.