Need help with terminology so that I can source a din rail version of this part
DIN is commonly used in industrial applications and, in Europe, in domestic fuseboards. Your DIN PSU will most likely be for industrial applications and will be priced accordingly.

I would be inclined to use the PSU that does the job at the price you want and modify it to mount on the DIN rail.



Figure 1. A quick search for "DIN rail clip" throws up plenty of options.