I find myself building a patio with 3 1/2 x 7 x 14" concrete "stones" for an edge. They weight about 28 lb with no good way for my old hands to grip them . I have regular brick tongs that can carry them, but they grip on the ends. I need to grip them on the sides to set them.
Using materials from my "may be useful someday" bin, I was able made a simple tool to grip the sides of the blocks. Now I can pick them up and set them with one hand. I have no dimensions for it. Yours would be different anyway since I put mine together with what I had around.
Below is a photo and simple drawings for your imagination.