I've had great success with PGA shirts. While I really like the Walmart Basic polo shirts (and they fit great), they didn't have that purple hue in their line.
Men'S Long Sleeve Polo Shirt - Slim Fit, Stretchy, Breathable Collar
43 Review
Calvin Klein π Herringbone Sleeve Men's Dress Clothing
50 Review
Men'S Regular Fit Short-Sleeve Dress Shirts By Allsense - Look Stylish And Professional!
41 Review
Gildan Performance Men's π Clothing and Shirts with Moisture-Wicking Polyester
44 Review