Give a set of military uniforms. Veterans must like these things. They can bring back memories of their youth and life in the military camps. If you can find photos of him when he was in the army and make a memoir, it will be even more perfect. This will be a treasure worth collecting in his life.
Give a copy of Mao Zedong's Quotations. People at that time especially admired Mao Zedong. This book must be your grandfather's favorite book. There is also a collection of pictures from the Anti-Japanese War period. Recalling the glorious years of those years, you will feel a lot of emotion.
You can also make some models of the Anti-Japanese War during your grandfather's period and put them on the table so that the old man can see them often.
The gift is not the most important thing. The key is the thought. As long as there is thought in this gift, then it is a good gift.