Profile resolutions

Hey - new to this but I’ve been looking for where the default resolutions
are kept - the reason I’m asking is I am encoding PAL material and nothing really matches the original 720x576 (I’m splitting out episodes on a series disk so I can access them individually - dont need much compression and would like to keep as much original quality as possible. The originals are anamorphic 16:9)

Are there PAL profiles around, or a file I can edit to add some more base resolutions? (add to base since I’m sill playing with various encoding schemes - once I settle on a encoding I could mashup a new profile I think)

Thanks!
jen