Go inside the project and find the sprite with the block you want. When you find it, drag the block and the definition for it into your backpack. You do not have to give me credit for these, but you can if you want to. Also, you can click on the tutorials button to look at the tutorial on how to change the colors of your Scratch blocks. PLUS: I am adding new blocks, so check them out!
I made all these blocks up (except for one, which I had some help with). If they are the same as some you made, that is just a coincidence. Great minds think alike! If you have any requests for custom blocks, I would be glad to make them for you.