Thank you so much!My '55 horns have those same model numbers so I'd say you are good to go. I have a 1956 edition GM parts catalog and it gives the following information:
1955 ALL, 12 volt, hi note (sea shell type)(stamped 760) part number DR-1999762
1955 ALL, 12 volt, lo note (sea shell type)(stamped 759) part number DR-1999761
Wow lucky they came with the carIn 1956 they cost $6.75 apiece. Adjusted for the cost of living from 1956 to today that would be 10.89 times that price or $73.51 each.