In this particular case, if you move and sew this section into place, select the UVs in the centre and unfold, it will put them back into place. As for general sewing of uv shells without distortion, there was a script called ESALsmartMoveAndSewUVs.mel from jocose…
nullfed, great I already had that script installed. Didn't know you could use it for that. Select two uv's on the smaller shell and turn on align shell, scale shell, and sew coincident uv's. Set the distance as high as needed.