Thanks - I was aware of sending-two-returning-one already, but I was unclear, so let me try clarify further
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I'm looking for a starting situation with no prior history (e.g. we first reached that situation via a sequence that for all practical purposes will not have any bearing on future possible repetition), where under correct play from that situation, the resulting score differs under the two superko rules.
The example you gave is not quite a starting situation whose result differs between the two superko rules in such a way, because under both superko rules under correct play the final score is still the same. PSK only prevents a black variation that under SSK leads to still the same result for black anyways.
Maybe it can be made to work with some arrangement of the rest of the board such that with SSK and other ko threats black can actually capture the two white stones because white has no non-self-harming board plays anywhere to be able to fight back, yet with PSK black cannot profitably begin this fight in the first place? If you could do something like this and get something like SSK leading to a black-owned corner and PSK leading to a seki, that would make a quite interesting difference, although I'd still be interested if there is any situation not relying on this sort of small-board pathology.