Model A1419 / EMC 2806 / Late 2014 or Mid 2015. 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (ID iMac15,1); EMC 2834 late 2015 / 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (iMac17,1) All with Retina 5K displays
It appears that a PSU for your Late 2015 27” Core i5 iMac can be found here for $74.99 used. Of course, Apple does not sell replacement units directly, so the secondary market (like eBay) is your only choice…
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