Evette Schaeffer Old Serial Number

Hi, have an old Evette Schaeffer Alto Sax Model # 7798 Brass in color. On the bell hsg is logo Evette over the word Schaeffer. Under Schaeffer is Paris over the word France surrounded by a leafy & Crown design. All the research I've done says 1st Buffet started company in 1866 then Crampon came on board to form Buffet Crampon Co. in 1871. Evette Schaeffer bought out Buffet Crampon in 1885 getting their own patent in 1867 starting with serial # 7xxx where Buffet Crampon left off. E/S went to serial # 29424 in 1927. My serial #fits in that period. Then I found nothing till 1952 where Buffet Crampon has Serial #'s 2925 thru 35733 in 1985 which my serial # 7798 would fall in 1961
My questions did Evette Schaeffer use their logo till 1927? How did Buffet Crampon come back in the picture? Who's logo did they use? Of all the pictures I found on the internet & E-bay, & while some I found are close to my serial #, none seem to match the log Evette Schaeffer Paris France Logo that I have. How do I prove which set of serial#'s am I looking at are for me?