Reddit mentions of Polo Ralph Lauren Mens Long Sleeve Slim Fit Stretch Oxford Buttondown Shirt (S, Optic Blue)

I have a similar build, and I tend to wear a lot of t-shirts. If you like logos, then Polo's custom fit t-shirts are a great option. You can get them for low prices on Polo's website (they're $16 each right now).

If you don't like logos, then J. Crew's broken-in t-shirts are a good option (albeit lower quality than Polo). Order a size down if you're getting the regular fit.

Basically, my strategy is to find a shirt that fits my waist and torso length and then just stretch out the shoulders and chest. This happens naturally as you wear them, especially if you wear them to the gym. Most of my shirts start out too tight around my upper torso but fit perfectly after a few wearings.

With sports shirts, unfortunately, you can't employ this strategy -- the chest and and shoulders won't stretch out over time. The absolute best shirts I've encountered are Ralph Lauren's slim-fit stretch OCBDs. They won't break the bank either: https://www.amazon.com/Polo-Ralph-Lauren-Stretch-Oxford/dp/B01EIK3VG2/ref=sr_1_1?s=apparel&ie=UTF8&qid=1474151813&sr=1-1&nodeID=2476517011&keywords=stretch%2Bsports%2Bshirt&th=1

Unfortunately, I tend to prefer clothing without logos, so I'm still looking for my perfect sports shirt.