Postal Stationery? St. P. Fr. In A Red Circle

I really can't figure this one out (in fact I have 2!). Printed on thickish horizontally laid paper, I was wondering if this was St Pierre et Miquelon, but not in SG.

Grateful for any guidance

I don't know where it's from,but probably not from St Pierre & Miquelon,or from France.
In french the official abbreviation for "Saint" is St or st , with no dot.

Hmmm, the mystery deepens.

with Vayolene. I collect St Pierre and have never seen that one before. Always see these - SPM, St-PIERRE M - ON

I just stumbled across the answer to this puzzle in my Michel Ganzsachen-Katalog Deutschland 1980!

It's Michel catalog number Braunschweig SU 1. The inscription stands for "Stadtpost – Franco" (Local post – Paid). This handstamp marked envelopes as prepaid for use in the Braunschweig (Brunswick) local post and was used from 24 Nov. 1844 to 31 Nov. 1867. The 1980 catalog value for a cut square was DM 10.

According to the catalog, forgeries exist. The genuine stamp is red with a diameter of 20½ mm. Reprints using the original handstamp were privately produced; these are characterized by a cleaner print and light tile-red color.

Nicely solved...well done you.

91/5000
I have similar, slightly bluish paper. I was also convinced that they were French colonies