I was wondering the same thing about the "star" jacket, especially re: the The Song Remains The Same concert film because Jimmy is wearing the star jacket to begin the show and the last that's seen of it is "Black Dog" and it's on to the "poppy bloom" jacket thereafter. The cinematographers' plan was to have Zep dress in the same outfits across the filmed shows for the sake of uniformity in editing but that was never adhered to. But the star jacket re-appeared for the Shepperton Studios filming which was done to supply missed concert footage by the original concert filming, which was include

That's a valid point re: a second guitarist although Zep RARELY ever used other musicians onstage. I believe that Atlantic Records VP Phil Carson played bass once, Richard Cole played tabla drums on "Whole Lotta Love" once and Keith Moon famously played drums once live at the LA Forum on 06/23/1977. But those were basically one-off performances and I don't think that Zep were very interested in using other musicians, and that of course made Page's job challenging for the need to be selective in his playing. Zep surprisingly pulled off "Ten Years Gone" in 1977 with Jonesy playing bass pedals

Check out Virginia Parker's website - she's an incredible painter and she still looks fantastic, too! Enjoy!