Joey wearing pants - is it realistic?

Absolutely. There's very little writing on the subject, which in itself could be considered evidence that it wasn't so outrageous, but we do have a lot of photographs of frontierswomen wearing trousers, most of which I can find are from the book Women in Pants: Manly Maidens, Cowgirls, and Other Renegades:

• Calamity Jane

  Professional scout and known for fighting Indians as well as her claim that she knew Wild Bill Hickok, both of whom were immortalised in Deadwood. This image is from 1895:

  

• Stella, Bertha and Mabel Sweet and Maybel Davis

  These 4 were the third group of women to climb Mt. Lyell and the first to descend into Tuolumne Canyon, this image from 1896 has them in leggings and bloomers:

  

There are also images of unknown women in trousers from the era, for example the name of this 1880s Arizona Scout has been lost, but it does suggest that men and women both wore the same type of clothing, as clearly a dress is not appropriate for battle or sleeping in the wilderness.