Swiss 87 Or 87A Or 87B Or 97 Or 110A Or 124...

Regarding the initial question:
The quickest way to figure out the stamp was to look at the date '87 and the number of teeth down the side, 14.
That 1Fr claret of yours stamp is part of the initial run and is a 11 3/4 perforation.

All the clarets are as follows.
1882 Zu.71A, Mi.63XA, Sc.87 - 11 3/4 - 14 teeth
1888 Zu.71B, Mi.63XB, Sc.93 - 9 3/4-9 1/4 - 11 teeth
1891 Zu.71C, Mi.63XC, Sc.87c - 11 1/2 x 11 - 13 teeth
1894 Zu.71D, Mi.63YC, Sc.87a - 11 1/2 x 11 - 13 teeth
1901 Zu.71E, Mi.63YD, Sc.87b - 11 1/2 x 12 - 14 teeth

Then the carmine 1 Fr were introduced.

Distinguishing between 87a and 87c is a major pain, and if there aren't post marks to help date it, then distguishing between the two watermarks certainly is a challenge. I'm thinking of printing the two watermarks dimensions on some sort of clear sheet that I can drag over the stamp to distinguish between the two. The best I've been able to do is measure the arms of the cross and comparing the lengths to the widths of the ends of the cross and that can definitely be no easy feat. Lindner and my father's album from his youth, just merge the two into one category and call it "good enough" regardless which of the two watermarks you might have. I have yet to delve into my mint collection to know if I have any of the original watermarks or they are all the newer version.

Just a follow up on differentiating between the two water marks. The width and length of each arm of the cross are like an inverse between the two. I've been able to make some headway in determining which watermark is which, using this method by getting an image of the watermark and measuring the length vs width of the arms of the crosses for comparison using Microsoft Paint .