Donald Trump’s campaign is auditing axed campaign manager Corey Lewandowski’s decision to buy T-shirts and other political swag from a pal’s Colorado-based company, campaign sources told The Post.

Federal records show Trump’s campaign paid $2.1 million to WizBang Solutions, a company based in a Denver suburb. The firm billed the campaign for printing T-shirts, “Make America Great Again” caps, yard signs, note cards and flyers, as well as postage and design costs nearly every month since April 2015, the records show…

As the campaign’s costs climbed, Trump officials complained they were paying WizBang about $8 per T-shirt, a source said. Lewandowski blew up when the officials suggested choosing a firm that could print shirts at one-fourth the price, the source added.