it is more likely that the pub starts with "03". I would omit the ones that start with "02".
Nice approach, but do you think there is any possibility to determine how often permutations occur and if there is a solution to find out any pattern of y parity, like if we could figure out how mant 02, and 03 keys exist in a certain range and if that could give us a pattern being repeated in all ranges.
That way we could use strides to ignore at least %40 of the whole bit range.