Sure, but for and height of 25px I cannot find anything. Is there, for example, a custom font community library, where user share various custom font made for Connect IQ?
Couple of things. With native fonts on some devices, when you look at appx B of the UX Guide, is some fonts on some devices, include a whitespace at the top or bottom, so a font listed as x pxls high, might show as x-y on the screen. The best way to see this is to just try them in the sim. The names are all the same between devices (the FONT_* and FONT_NUMBER_*), but the fonts themselves are different.
If you can't find a font that works for you, it's pretty easy to create your own custom font with bmfont. I often use 1001freefonts, and find one that I want to use and create a custom one for CIQ in just a couple minutes. (bmfont is discussed in the Programmer's guide) There are also a number of threads here where custom fonts are also discussed - most recently about having something smaller than XTINY on Fenix 5 devices.