It's not hard to find small quantities of various metals, as long as its under, say, a couple pounds of it. That sort of thing can be purchased at any metalworking business, though you might get odd looks about it. Unlike the crystal that the domes are made of, the metal types aren't a restricted substance, and in an industrial city like Khatronma, they already have decent amounts on hand. So it's won't be exorbitantly expensive, and certainly the Bresilykians would be willing to exchange some labour for it.