hitoshi kiyohara cartoonish woodblock prints?

I bought these today at the Goodwill in ugly pink frames for 10 bucks, just because I thought they were cute. After doing some research the artist is hitoshi kiyohara, and possibly original woodblock prints? I took one out of the frame to look at the back which is the second picture. They both have a red stamp in the right corner, but the fireworks one has possibly a signature, I don't know. From what I have read they are from the 40's or 50's, and in excellent condition if they are indeed that old. Thank you for looking!