After the dissolution of the Soviet Union in 1991, the international market was flooded by postage stamps supposedly issued by various ex-Soviet regions. These stamps are bogus. The Russian Federation has even issued official statements pointing out that only centrally produced Russian stamps are valid. The stamps from Sakhalin Island are no exception. Note the text in English!
By all means, buy these stamps if you like Bearded Collies or weird stamps (I think both phenomena are pretty cool myself), but note that you probably can't sell them to a professional collector of real Russian stamps, should you be able to find one in your hometown.
Personally, I'm fond of the almost-bogus stamps from Staffa, a small islet off the Scottish coast mostly inhabited by sea birds (the goats were removed a couple of years ago), or the super-bogus Nagaland postage stamps, showing European Baroque art (yeah, like the average Naga guerrilla warrior gives a damn).
Who knows, maybe even this series of dog-related "Sakhalin postage stamps" will bring back some fond memories when you're 50.
If not, you can always procure a real Bearded Collie.