When I riveted my new leather hood-corners, I used this brake lining rivet tool sold through
Brattons. It comes with several different rivet setting tools and one of them (the one shown in the middle of the below picture) worked perfectly for the leather hood-corner rivets. It is totally portable (the size of your hand) and thus no need to remove the hood from your car.
I also used the same tool to secure the rivets that hold on the
hood latch bumpers as well.
Brad in Maryland