Due to declining health and a serious health issue a few years ago, I have already given much thought to passing on sometime in the future. Though, having the money the op states and only 10 days, I would begin giving much of it away, establishing trusts, various foundations, making sure all my various family were well cared for, my religious org, etc, etc. Money and material wealth serves no purpose in the grave, and quite frankly with only ten days, I would not spend much on myself.
I would plan a simple funeral with a simple coffin, maybe take one last trip with family and to the place I wish to die and be buried. Enjoy treating family and friends to great views, good food and sharing many memories of times past. Then when that final day comes, I would sit on a mount and enjoy one last sunset.
Of course and if he wants them, all my firearms and reloading and shooting supplies would go to my son, but if he doesn't want them all due to not being the hunter nor shooter I am/was, I would make a few other people happy.