TD;DL The stand for an similar iMac such as a Late 2009 iMac 27-Inch A1312 will attach to and work with a Mini Displayport Cinema Display ( A1316 ) or Thunderbolt Cinema Display ( A1407 )
Although Apple now offers the XDR Pro display many are still using and opting for the old 27″ 2K Cinema Displays such as theMini Displayport Cinema Display ( A1316 ) or Thunderbolt Cinema Display ( A1407 ). Although the new XDR appears to have great specs, the $5k-$6k cost puts it out of reach for many, while both of the 27″ 2K models are still readily available on Ebay for around $200~$400 and even have a webcam which the XDR display does not.
The typical price range for a 2K Display in good shape and working order is typically around $300 or so. When you’re looking at one make sure to pay close attention to the edges as that is where you typically see chips. Also take a very close look at the corners as those also tend to get dented in and that makes the glass not sit correctly.
If you are willing to deal with some imperfection less pristine examples can be had cheaper. A good example of the types of issue you may see are 2K Displays that don’t have a stand or that only comes with a VESA mount. On these types of displays you had to remove the stand to use a VESA mount. As a result you will find displays that you can save money on by purchasing an example without the stand. The bad news though is the stands for these displays are rare and often fetch up to $100. On the other hand the iMacs of similar vintage look visually the same. Which lead to a question:
Can I use an iMac stand with a Mini Displayport Cinema Display ( A1316 ) or Thunderbolt Cinema Display ( A1407 )?
Yes, you can. The serial number of the display/iMac is on the bottom of the stand so that won’t match anymore, but other than that I have been able to find no difference between them. The screws even appear to be the same. I was also able to detect no height difference in the display using the iMac stand when compared to a display that had a matching stand. The best part is that these can be had for as little as $20-$30 dollars vs the $100 for a stand that is specifically for the display!
A word of caution for working with a iMac or even a Display with the stand off. If the mounting plate that slides in and out of the display is pushed back into the display with the stand off it will lock inside the display! To get it back out you will either have to take apart the display so you can push it back out from the inside or somehow get your hands on an Apple technician tool specifically designed to slide in and pull the mounting bracket back out.