One can list a bunch of written records pre-dating at least most of the Old Testament books, but the real argument is this: written records with similar ideas pre-date the Old Testament, therefore, the OT borrows. Frankly, this is bogus.
1 - As far back as the writings in question are, the ideas written down were not original, that is, they pre-date the writings.
2 - The Judeo/Christian narrative clearly makes claims of reaching much further back than the writings you cite. Suggesting that these writings disprove that narrative requires that the narrative have been previously rejected in order to accept the idea that these pre-dated records represent an earlier origin of the ideas rather than the actual distortions. This is circular reasoning. If you have other reasons for your initial rejection of the Judeo/Christian narrative, please present them.
Moses and Sargon
As for the story of Moses, that's a historical event, not a philosophical, spiritual, or religious concept. If it is true that Moses's mother borrowed an idea to save Moses from a historical legend, that does not in any way imply that religious tenants were appropriated. Furthermore, while Sargon's suspected life time may predate the life of Moses, the apparent source of the legend that we have is not so old. According to Wikipedia, the source of Sargon's legendary basket ride is a tablet dating to the 7th century , which does not predate the events of the Exodus account. If mere historical appropriation occured, it could have occurred in either direction.
My understanding of Occam's Razor or the Principle of Parsimony is that it essentially states that "one should posit no more entities than are absolutely necessary". As a result, I've never found it's application as an argument against the existence of a divine being at all compelling. Anyone who accepts the razor as an argument clearly believes God is not necessary. Those who believe He is, include Him.
Natural Laws are adequate for explaining a great deal of the world in which we live, but there is much that such Laws do not seem capable of explaining or giving significant meaning to, such as why there is something rather than nothing and absolute morality.
In other words: application of Occam's Razor requires a reason to believe the denied entity is not necessary. Make that argument instead.
 "Sargon of Akkad". Wikipedia.