Small Queen First Print Ottawa Or Montreal?

I have obtained a small group of the so-called Small Queen, and I have begun to turn my head crazy with them...I would like to show you this specimen that I think has many characteristics to be able to determine which impression it belongs to.
The copy has:
-12x12 perforations
-Dot position in the lower left corner
-White paper with a visible grain mesh.
-Partial cancellation of Montreal, possibly from the year 87 but it could be 77
-The color is clearly with an orange shade without a trace of yellow.
In my opinion it is a first impression of Ottawa or Montreal...From the postmark I would say it is Montreal, perhaps the determining factor is the paper but I do not yet have the knowledge to determine it...

I'll let others guess as to print period - I have some idea based on the paper I see - but the "7" in the split-ring cancel (almost certainly Montreal) is not part of the date, it is probably a time mark or routing mark. Others more knowledgeable are welcome to chime in.

(MONTR)EAL
( )7
(JU)N 6
(A or P)M
(C. or QU)E

If it is orange 12 x 12 it is an early Ottawa printing.
1870 printings are perf 11.9 x 11.9
1870 to 1872 are perf 11.85 x 11.85[
later 1872 printings are perf 11.8 x 11.8
GJP

Thanks for the help. I would have opted for the first Montreal issue based on the readings I have done these days on the subject, since the mesh of the paper is too clear to the naked eye and it was also issue with 12 perf.