Looking at all #reddit users up through June, 2015 (33.5 million users) and excluding 0 karma users (most likely lurkers):
Comment karma:
Mean: 1,565
25th Percentile: 2
50th: 20
75th: 281
Submission karma:
Mean: 948
25th: 2
50th: 21
75th: 237
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99'th percentile for Submission and Comment Karma (excluding 0 karma users)
Submission Karma: 13,243
Comment Karma: 22,747