numsrs Since each die was punched individually - die varieties are rarely considered unless the repunching is very significant. Most simple repunching of letters or numbers with the same letter or number is common and adds no value at all. At times a very wide repunching can become collectable but the premium is usually very small to none.
From the pictures of the edge, I would suggest two tests to confirm that the coin is genuine. First specific gravity. The SG of a genuine 8R is 10.31. Any deviation over 0.01 is potentially a grounds for concern.
The second test will be far more definitive. Find a large coin dealer, jeweler or dealer in metals (even a good junkyard) and see if they will do an XRF test of the coin. The XRF is non-destructive and can be used to detect a trace of gold. All Mexican coins struck during the colonial period in Mexico City will show a significant trace contamination with gold. The state of the art at that time prevented the removal of all traces of gold from silver that was recovered using the Patio Process (mercury amalgamation). No amount of cupellation will reduce the gold to result in 99.99 pure silver. So if the XRF reading shows no gold present (0.00% gold - two decimals) you have a made for China silver restrike.
Based on visual clues from the edge, I say your chances exceed 50-50 that the coin is NOT genuine. The period of likely manufacture is somewhere between 1870 and 1930. If could be newer however, there is only a small chance it is genuine and was struck in 1802.
My book on Counterfeit Portrait 8Rs is available from Amazon http://ccfgo.com/TheUnrealReales
or from me directly if you want it signed.