Quoted from SantaEatsCheese:... but not on what order things should be done.
A. Play the crap out of the game before messing with the area
B. Remove insert jewels and sand down tops smooth.
C. Apply some sort of filler to raise playfield here to slightly below level of surrounding paint.
D. Re-insert removed insert jewels.
E. Apply polish/rust remover to metal scoop hardware.
F. Add filler/putty to scoop area.
G. Apply touch up paint to area around scoop.
H. Paint area around inserts
I. Apply water-slide decals to inserts.
J. Apply shaped mylar to area around smooth.
K. Apply Cliffy.
L. Play the crap out of it.
Z. BUY A NEW REPRODUCTION PLAYFIELD.
Based on the picture, I would pick option Z.