When I got my first "parlor" guitar, an Ibanez PN1-MH, I took it to my area luthier to see if he had a gig bag that would fit it. He did. A TKL 04675/BL. That bag is advertised for "three-quarter"-sized guitars.
It fits the Ibanez PN1s with plenty of room, but not enough to let it "slop around" like it would in a full-sized gig bag.
It fits the Washburn size 0s like it was made for them. It also fits the Luna Gypsy Parlor, although it's length is just a tad "tighter" due to the two extra frets.
It DOESN'T fit the Ibanez PN12E, which is about a size 00.
Here is the bag on Amazon (I get a few cents if you buy it through this link but you are VERY welcome to shop for a cheaper price elsewhere):
https://www.amazon.com/TKL-4675-Traditi ... s_li_ss_tl