I googled "protogermanic grammar" and immediately got a truly fine site: http://www.utexas.edu/cola/centers/l...gmc03.html#3_2
There was a table there:
3.2.5. The nt- stems
PGmc Go. ON OE OHG
Nom.sg. frijund frijōnds frændi frēond friunt
Gen.sg. frijundiza frijōndis frænda frēondes friuntes
Dat.sg. frijundi frijōnd frænda frīend friunte
Acc.sg. frijundun frijōnd frænda frēond friunt
Nom.pl. frijundiz frijōnds frændr frīend friunt
Gen.pl. frijundōn frijōndē frænda frēonda friunto
Dat.pl. frijundmiz frijōndam frændom frēondum friuntum
Acc.pl. frijundunz frijōnds frændr frīend friunt
EDIT: I can't copy and paste it so it looks like a proper table, it seems. You can easily find it on the site, though.
By the way, I realise that my half-assed google search doesn't prove anything; I'm hoping that a knowledgeable forum member will come and clear this up.
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