Are there reproductions available of any of the paintings in the Jordan River Temple?

I would reach out to suppliers of art to deseret book. Altius Art in American Fork has had art work that DB didn't have or no longer carried. There are several suppliers.

There are quite a few Walter Rane pictures there. Those are pretty much only available at the Church History Museum in Salt Lake. They sell prints of the pictures the church has exclusive rights to, many of which you can't find at Seagull or Deseret Book. I would check the museum if you can't find the prints you are looking for at one of those stores.

I don't know, but the ones of women in that whole dressing room area are poignant

LDS book and art stores like Seagull Book or Deseret Book have vast selections of art, including some of the art being displayed in temples.

Probably of most of them. Try going to Deseret Book or Seagull Book. Describe the painting and see if they can find it for you.