There are two things you could do. I would try to find the original metric screws used for the pickup height adjustment or you could tap the metric height adjust holes for “National Course” American Threads. Fender pickups made in the USA are normally threaded 6/32. The (6) is the diameter of the screw and (32) is the threads per inch. You need to drill a hole before you can tap it. Below is a standard chart for screws and taps used in guitar pickup construction. The tap size is the same as the thread in a screw.

National Fine National Coarse

Tap Size Drill Size Tap Size Drill Size
0-80 3/64 1-64 53
1-72 53 2-56 50
2-64 50 3-48 47
3-56 45 4-40 43
4-48 42 5-50 38
5-44 37 6-32 36
6-40 33 8-32 29
8-36 29 10-24 25
10-32 21 12-24 16
12-28 14 1/4-20 7
5/16-24 3 5/16-18 F
1/4-28 1 3/8-16 5/16
3/8-24 Q 7/16-14 U
7/16-20 25/64 1/2-13 27/64
1/2-20 29/64 9/16-12 31/64