Hi Hugh,
I LOVE real ivory grips, I just don't think I can afford them for a Luger...or any other gun I own for that matter...even for just display. I would be afraid that shooting a Luger wearing those might crack the grips... and that would HURT.
I own one gun that has genuine ivory grips. A Colt Peacemaker in .44-40. The gun was a gift from my in-laws. It had been in their family since it was new...(1884 I think) and I have the shoulder holster it was carried in to protect the family store in southwestern Missouri. They had two sons but neither liked guns so they gave it to ME! God is good and he smiled on me that day! The great aunt that was living at the time I received the gun (she was 89 at the time) told me that she remembered that her father took the gun out of the cedar chest on November 11, 1918 and fired all the ammunition they had in the house at the time up in the air to celebrate the armistice for WW1. Then (without cleaning the gun!) he put it back in the holster and back in the cedar chest where it remained until it was given to me around 1984...The grips are original. I love the way they feel in my hand.
When I get a chance I will post a photo of the gun...my digital camera is down and I will have to use the scanner... I did a lot of work to make the gun look presentable... it was pretty rusty after sitting with black powder corrosion in that cedar chest for all those years. The grips have a nice yellow color to them. my preference would be for smoothe ones instead of carved or inlaid designs in case you are taking notes on what to give me for Christmas