Goldberg, Max, b 20 Jan 1893, d 8 Aug 1970 Dallas Co, TX; last residence Dallas, Dallas Co, TX; SS card issued in OH. [TX Dth Idx listed him as single, but I have learned that sometimes can be misleading, lots of errors on the index.It also can mean separated or divorced, too.]
You might try the Dallas Pub Lib for an obituary on this Max.It might give enough information so you can tell whether he is yours or not.
On the TX 1930 census there are 3 Max Goldbergs born in Russia, but the youngest is 49.From birth year of your father, I think all of them are too old to be your Max, maybe yours came to TX later.SS cards weren't distributed until the 1930s, the above Max obtained his in OH, sohe may have been in OH for the 1930 census.I don't have access to 1930 OH census, you might post on the Record Lookups forum, see if someone can find him for you.Go up and click on My GenForum, click on General Genealogy, click on Record Lookups, and post your query.
On the 1910 census for NY, when your Harry would be five, there are 110 Morris Goldbergs born in Russia, 73 of them are in NY Co.The name is even more common then I thought.