there are a few people here who are more knowledgeable about the older kukhri's, and the touristy ones as well, you may also want to have a look and post over on the International Kukhri Research and Historical forum
valuations are not discussed here but i also think the price is a bit high.
cows would not be sacrificed as far as i know, water buffalo maybe, goats are, but smaller (ie. 18in-24in.) khukris are more than adequate (i will not post pictures or links, but the kami's who make the khukris frequently sacrifice goats to bless the steel, they use a std. everyday model). many of larger ones engraved and coin decorated ones are tourist decorators. this may have been made for a temple ceremonial purpose, but i'm not up on that end of the market, only weapon and village tool ones.