In OSRS, before bonds (their equivalent of tokens) were released, there was a strong gold industry, but most people who bought gold did so by buying bonds on the main game, then finding a dedicated 'swapper' who'd exchange their RS3 gold for an appropriate amount of OSRS gold (taking a cut for themselves, of course). I wonder if a similar system will pop up in classic wow
Where to get materials and reagents you may ask? Buy for cheap off farmers in bulk or track Auction House lots. Get in touch with most big sellers. Communication is important here, send a whisper or write them a letter. It would be good for both of you to establish business relationships. Constant suppliers and buyers is convenient for both parties to save the time and effort.