Scoring records do start from 1907 officially by the SANFL. I would prefer them to start from 1899, because this is the year when electorate football became compulsory and not in 1897 when it was first introduced.
The 1.4 (10) match:
viewtopic.php?f=17&t=20096 is the lowest score for Port from 1907 onwards. However, taking 1897-1906 into account, the lowest score is actually this one:
Round 1 1900
North 0.1 3.6 4.9 6.10 (46)
Port 1.0 1.0 1.0 1.1 (7)
Alberton
The lowest five scores for Port are:
1.1 (7) vs North 6.10 (46) Rd 1 1900
1.2 (8) vs Norwood 4.10 (34) Rd 9 1900
1.4 (10) vs South 16.7 (103) Finals Section 1 match 1899
1.4 (10) vs Norwood 0.5 (5) Rd 3 1909 - lowest winning score
1.5 (11) vs Torrens 2.4 (16) Rd 2 1900 - lowest winning score Port have conceded
Taking the 1897-1906 scores into account, the 15 points scored for the match is still the lowest match aggregate on record.
The number of scoring shots for the match is equal 2nd:
Round 2 1898 (7 scoring shots)
Port 0.0 1.2 1.2 2.3 (15)
North 1.0 1.0 2.0 2.0 (12)
Alberton
Final 1919 (10 scoring shots)
North 1.0 1.0 2.2 2.3 (15)
Torrens 1.1 1.3 2.3 2.3 (15)
Adelaide, 10000