I just went through this exercise recently, and ended up purchasing a power supply that I think is very good.
I had previously purchased a cheap power supply on Amazon for about $30. It was a Chinese made unit that worked, but I didn’t feel after using it, that it was capable of providing stable, protected power to my expensive avionics. After using it for a short time, the voltage adjustment pot failed, and I ended up soldering the pins that I assumed would give me 14+ volts. It only actually gave me about 13.4 volts, and still had me wondering on the stability/safety of the power it was supplying. I don’t have any evidence that it wasn’t working, but I just didn’t trust it. So I went searching.
The first place I looked was the White Lightning power supply - available at ACS and Sporty’s (near me). This is a rock solid unit that you can trust to supply stable, protected power to your airplane. I know John Sisk, owner of the company that makes this power supply. At $475 for the experimental version (certified version is more). There are several others that are much more expensive than the White Lightning. I decided to look further to see what was available. My research turned up a power supply made in Japan that is used by ham radio guys who need a 12v power supply for their bench mount, non-handheld ham radios. The one I decided on is the Alinco DM-330. It is a 30 amp (continuous), 12-15v, protected power supply. It is made in Japan, and I trust that. All of my favorite TV’s have been made in Japan, and I bought it from a ham radio shop near my airport that guarantees it. It was about $200 with tax here in Ohio. There are other ones available if you look, but this one works for me.
https://www.dxengineering.com/parts/alo-dm-330mvt?rrec=true
Good Luck with your search. I would caution you about buying cheap imitations. The one I bought is also available for a cheaper price - cloned - but made in China. It looks the same, but isn’t.