Amazon has a bunch of MLB shirts at clearance prices. Many of them are "Add-on Items" so you’ll need to spend at least $25 or more before checking out.
All of them are Prime Eligible as well.
**Prices can fluctuate widely based on size and team choices. In most links, you can choose other teams and sizes to see prices.
All MLB T-Shirts: https://www.amazon.com/s/ref=sr_s…nceb
Some samples:
MLB Signed T-Shirts – From $1.94
https://www.amazon.com/s/ref=sr_s…e-asc-rank
Youth Boys T-Shirt THREE PACK – From $8.15
https://www.amazon.com/s/ref=sr_s…e-asc-rank
Los Angeles Angels Stadium T-Shirt – $2.99
https://www.amazon.com/gp/product…UTF8&
San Diego Padres Stadium T-Shirt – $5.20
https://www.amazon.com/gp/product…th=1&
LA Angels T-Shirt $5.91
https://www.amazon.com/gp/product…th=1&
Angels T-Shirt – $4.76
https://www.amazon.com/gp/product…UTF8&
Kansas City Royals T-Shirt – $5.46
https://www.amazon.com/gp/product…th=1&
St. Louis Cardinals T-Shirt – $4.48
https://www.amazon.com/gp/product…th=1&
San Diego Padres T-Shirt – $5.78
https://www.amazon.com/gp/product…UTF8&
Cincinnati Reds T-Shirt – $4.55
https://www.amazon.com/gp/product…th=1&
San Francisco Giants Signed T-Shirt – $3.53 (Large Only)
https://www.amazon.com/Francisco-…B01L3ON4BI
Pittsburgh Pirates Signed T-Shirt – $2.72 (XL only)
https://www.amazon.com/Pittsburgh…B0
MLB Men’s Football Style Tee – From $4.21
https://www.amazon.com/MLB-Mens-4…B01G8P0SZM
MLB Crosstown Flanker Tee – From $2.87
https://www.amazon.com/MLB-Mens-4…B01GGKK3KE