Increase in vertical res: 1.2x
Target vertical res: 352 (approx.)
NTSC Source vertical res: 272 (approx.)
PAL Source vertical res32.: 326 (approx.)
Needed vertical scaling when converting to NTSC/A: 10.43% (approx.)
Needed vertical scaling if sourcing from NTSC: 32.35% (approx.)
Even though you'd still need to resize, the scaling wouldn't be as drastic. If your source image actually *had* 326 scanlines... all the better!