Using such sources, a deft modern forger has the essentials regarding script, orthography, vocabulary, syntax, language, and culture to produce a fine Old Hebrew forgery. All of these sources are widely considered standard in the field and are readily available; therefore, knowledge of, and access to, the proper resources is not an issue (and such sources are available for all the Northwest Semitic languages, not just Hebrew). Forgers also now have available software programs (e.g., Adobe Photoshop) that can be used to facilitate accurate "script production."I noted the article here back when it came out. Some of the many, many related PaleoJudaica posts are here, here, here, here, and here and links.
Some of the remaining requirements would be adequate time; some knowledge of, or expertise in, chemistry or ancient metallurgy (or an associate with such expertise); access to various materials such as potsherds, ancient metals, stone of Levantine quarry, small pieces of ancient papyrus or vellum, some carbonized remains (for the production of "ancient" ink), and sufficient finances. None of these necessities is problematic.
Because non-provenanced epigraphs often sell for thousands or tens of thousands of dollars, funding is not a major issue; that is, the sale of one forgery could fund the production of several additional forgeries. Moreover, ancient materials of various sorts are readily available to those participating in, or associated with, excavations or those dealing with the market. In addition, the chemical composition of ancient patinas can be replicated.
Rollston's 2005 article demonstrates that long before the fake metal codices or the Gospel of Jesus' Wife emerged, specialists were well aware of the danger of forgers using ancient materials such as lead or papyrus to create fake artifacts with an appearance of antiquity. Good call, Chris.