I haven't found the arxiv for this, but Anton Wallner in Germany has at least issued a press release. This is looking at iron-60, an isotope nobody is making here on Earth. Supernovae make it; and Wallner has measured some. The assumption is the implosion of a giant, not the Type 1A "standard candle" explosion of a dwarf.
Based on iron-60's halflife, I guess Earth got this iron over here 7 Mya and 3 Mya. The supernovae can't have detonated within ten parsecs, or we'd never have been born (probably). But they can't have been all that far away; so the material is presumed to have been created not geologically longer than 7 Mya and 3 Mya.
Note: not the Local Bubble creation. That formed 14 Mya. We're in the middle of it now. The solar apex is toward Hercules (north of zodiacal Ophiuchus) so, we're moving more orthogonal even toward zodiacal Hyades than away, strictly-speaking. Back 14 Mya, that supernova was in or around Hercules, relative to us. The bubble's creation could well have formed the giant stars which went boom 7 Mya and 3 Mya.
I don't think giant stars move very quickly from their "stellar cradles". The two stars as supernova-generators would not have formed in the first place long before 7 Mya and 3 Mya. Were we, ourselves, closer to such a cradle? Close to the Bubble's edge...?
As to these two neutron-stars or even [12/20: for the 3 Mya] black holes - I don't know how far they've travelled since.
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