The generator matrix

 1  0  0  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1 2a  1 2a^2+2a  1 2a^2+2a+2  1  1 2a  1 2a^2+2  1 2a^2+2a+2  1  1  1  1 2a^2+2  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  1  0 2a^2+2 2a 2a^2+2a  2 2a^2+2a+2 2a+2 2a^2  1 2a^2+a+2 a^2 2a^2+3  3 2a^2+2a+3 2a+3 2a^2+2a+1 2a^2+1 2a+1 a+2 2a^2+3a+2 3a^2+2 a^2+2  1  a  1 3a^2  1 2a^2+3a a^2+2a+2  1 3a^2  1 2a^2+a  1 3a+2 3a^2+2a+2 3a^2+2a+2 3a  1 3a^2+a a^2+3a+2 a^2+3a 3a^2+3a 3a^2+3a+2 a^2+a a^2+a+2 3a^2+a+2 a+1 3a+1 3a+3 2a^2+3a+1 2a^2+a+3 2a^2+3a+3 a+1 2a^2+3a+3 a^2+a+3 3a^2+a+3 a^2+3a+3 a^2+a+1 3a^2+3 a^2+2a+3 a^2+3  0
 0  0  1  1  a a^2 3a+3 a^2+3a a^2+3a+3 a^2+2a+1 a^2+2a+3 3a^2+2a+1 a^2+1 a^2+3a+1 a^2+a a+1 a^2+2a a+2 2a^2+3 2a^2+2a+2 2a^2 2a^2+2a+3 3a^2+3a+1 a^2+3a+2 3a+3 2a^2+3a a^2+3a+2 3a^2 3a 3a^2+a+3 3a+1 3a^2+a+3 2a^2+a+2 2a+1 3a^2+a 3a^2+2a 2a^2+a+1 2a^2+3 2a^2+2a 3a^2+2a 3a^2+1 2a+2 3a^2+3a+3 3a^2+2a 3a^2+3a+2 2a^2+2a+3 2a^2+3a+1 2a^2+3a 3a^2+2a+1 3a 2a^2+1 a^2+3a+2 2a^2+a+3 a^2 a^2+3a+1  2 a^2+3 2a a+1 3a^2+3a+2 a^2+2a+1 2a^2+a+1 3a^2+2a+2  a  2

generates a code of length 65 over GR(64,4) who´s minimum homogenous weight is 438.

Homogenous weight enumerator: w(x)=1x^0+2688x^438+5544x^439+7287x^440+448x^441+336x^443+560x^444+14280x^446+24080x^447+28343x^448+1568x^449+1120x^451+1120x^452+22960x^454+28392x^455+22806x^456+2128x^459+1904x^460+28168x^462+35168x^463+31661x^464+1568x^465+7x^480+7x^488

The gray image is a code over GF(8) with n=520, k=6 and d=438.
This code was found by Heurico 1.16 in 12.8 seconds.