I bought them from amazon. Pack of 6 for $9 with prime shipping(from china $3 free shipping). All of this minus phone and headphones can be bought from china for less than $20.

Link(dont know why it has bad review. He doesnt explain) https://www.amazon.com/Sterling-Ultra-Thin-Anti-Sweat-Breathable-High-Ranking/dp/B07THHNK2Q/ref=mp_s_a_1_6?keywords=clingparty+sleeves&qid=1567899040&s=gateway&sr=8-6