Vintage screenprinted T-shirt

Small baseball style T-shirt probably from the 70s. It features several common motifs of the era such as rainbows and flowers, as well as famous WWII graffiti character 'Kilroy.' Has some discoloration in the armpits that can be fixed by soaking it in vinegar and rubbing some baking soda on it gently before washing on delicate cycle. Tag is extremely faded but I believe says "Loyal Army." Shirt is definitely small.