I hate to have to tell you this, but there isn't really such thing as a $2 shirt, please hear me out.
The monetary cost to you, acting as a consumer is an incredible $6 or, $2 a shirt; However, as a citizen of earth, the environmental and social costs of buying cheap garments from places like Walmart is absolutely, shockingly enormous. [1][2]
It's just currently impossible to produce clothing at that price in an even slightly responsible way. Unfortunately, buying super cheap garments is really taking out a loan out against the future and that bonded or forced labour is probably involved. [3] If you're a documentary person, "The True Cost" is really worth watching. [7]
There is a few apps that can help people make informed choices before a purchase [4][5] and of course, great brands like Patagonia [6] who make quality clothing in a responsible way.
There are also amazingly good quality items in second hand stores around the world too, I know there can be some stigma attached to second hand clothing, but it's only stigma, it wears off quickly and no one knows you have a second hand shirt on.
I have a friend who works at a second hand store, which is part of franchise, and there are a lot good quality, safe items in surplus around the world waiting to be worn again.
[1] http://source.ethicalfashionforum.com/article/introduction-t...
[2] http://source.ethicalfashionforum.com/article/introduction-t...
[3] http://labourbehindthelabel.net/campaigns/living-wage/
[4] http://goodonyou.org.au/
[5] https://rankabrand.org/
[6] http://www.patagonia.com
[7] http://truecostmovie.com/