Chosen Solution
Is it possible to replace the stand on the 2013 21.5"iMac Ultrathin?
If you are looking to go with a VESA mount sorry to say Apple doesn’t offer the parts. Apple does offer the standard foot as a spare if your’s is damaged. To replace the standard foot will require completely disassembly of the system. This is a very big job! I would recommend you bring your system in to an Apple Store or authorized service center and let them do it as it will be cheaper and less risky.
No it’s never been done but you might be able to find something that you can do such as take out some screws or some clips from the back of the iMac if not there is no way to replace them and if you find a way please post a repair guide so I can help some of my costumers that have asked the same thing. If this answer helped please give it a thumbs up .
It is possible to buy a new iMac with a VESA stand: http://www.apple.com/shop/buy-mac/imac-v… So maybe if you ask apple, they can switch the stand. As far as I know, that’s your best option.