The pants would be hard to find elsewhere due to their unique design, so if you really like them, get the pants. The blazer can be found cheaper at another store and a basic white T-shirt can be found in like every clothing store so both of those wouldn't be worth big bucks.
I think its a great outfit and u should definitely but it omg. The pants contrast with the color of the blazer, that makes it so great. And I mean white t-shirt just looks cute on any guy soo lmaoo. Seriously go for it!