Antique Lamp Identification

This was my grandmother's lamp. I am not sure how old it is but I do remember it always being in my grandmother's house from time I was born. Had she lived, she would have been 120 years old. She got this lamp shortly after she married and set up housekeeping which was at the age of 21. This lamp set on the table in her living room but when she moved in with us after my grandfather died, my brother put some of her belongings in the attic. After she died, I told my brother that I wanted this lamp. When he went to the garage where some things got moved, a couple of the panels in the shade were broken. Thinking the lamp was no good any more, the shade got thrown out and I ended up with just the base. I am looking for a shade to go on this lamp and I want the right kind that is supposed to be on this lamp. I found one that I liked on E-bay, but do not want to buy it until I know more about this lamp. I have looked everywhere for any kind of mark or signature, but do not see anything. Underneath the base where it has not discolored from age is a bronze color. You can see that it has turned dark with age. I plan to clean it once I find the shade. The width of the base is 7 1/4" and the height overall is 23 1/2" tall. The fitter is 3 1/2" wide. All the information provided to me will be greatly appreciated. I want to put this on my table just as my grandmother did. I wanted to show the entire lamp but it must be too tall cause it will not let my picture rotate right. It is sideways.