That 40 Reis 1829-R is definitely a counterfeit from that time. The stamp over it seems to be a "Pará" counterstamp. This very rustic type of counterstamp was struck as an urgent measure, to pay the troops supporting the revolution. First they took the coins (just the provincial ones, struck in Goiás(G) and Cuiaba(C)) that had been traded for banknotes from the treasury of the province. After the first leader who ordered the counterstamping was killed another leader also ordered that the remaining coins (struck in Rio de Janeiro(R) and Bahia (B)) were to be stamped.
The stamp over the 80 Reis was struck later we call it "Carimbo Geral"(general counterstamp), some believe the the Pará counterstamp was a precursor of the general counterstamp.
There are also other provincial stamps associated with revolutions in this period.
Here's the wikipedia article about this revolution:
https://en.wikipedia.org/wiki/CabanagemIn the photo you can see:
1. 20 Reis 1827-R with the Pará stamp (10)
2. 40 Reis 1825-R with the Pará stamp (20)
3. 80 Reis 18?-R with the Pará stamp (40)
4. 40 Reis 1830-C with the Pará stamp (10)
5. 80 Reis 1826-C with the Pará stamp (20)
6. 80 Reis 18?-R with the Ceará stamp
7. 80 Reis 18?-R with the Maranhão stamp (1st type - MXX)
8. 80 Reis 1830-R with the Maranhão stamp (2nd type - M)
