Consider 2 cases:

case 1: When units digit is 2, 4, or 6: n 1=4x8x7x6x3=4032 case 2: When units digit is 0 or 8: n 2=5x8x7x6x2=3360

n=n 1+n 2=7392

so last 3 digit is 392

python

ans = []
def iseven(n):
    if n % 2 == 0:
        return True
    else:
        return False

 def repeatdigitdetected(n):
    a = []
    b = []  
    if type(n) == int:
        n = abs(n)
        for i in str(n):
            i = int(i)
            a.append(i)
        for i in a:
            if i not in b:
                b.append(i)
        if a == b:
            return False
        else:
            return True
for i in range(20000,70001):
        if iseven(i) == True and repeatdigitdetected(i) == False:
               ans.append(i)
 print len(ans) % 1000

that prints the answer $\boxed{392}$ :-)