Chara-Ani is releasing a new collection called Godzilla 66, which is not what Americans may think (as in Route 66 although that does work) as it is a representation of Godzilla's design shape. The line includes t-shirts, towels, a mug, can badges, and clear files, items range in price from 440 yen up to 3,300 yen, and the will be released in May 2021. They can be ordered direct from Chara-Ani and the Godzilla Store as well, both offer unique stickers as a bonus (with 2,500 yen or more purchased).
Update: a few more items have been added (images at bottom).