Army Undersecretary Michael Obadal purchased between $1,001 and $15,000 worth of SpaceX stock, according to a disclosure. Silas Stein/picture-alliance/dpa/AP ImagesSpaceX celebrated its initial public offering in June by selling hundreds of millions of shares — and making Elon Musk a trillionaire.Among the buyers that day: Army Undersecretary Michael Obadal, who purchased between $1,001 and $15,000 worth of SpaceX stock, according to a financial…