venturisadf support real small-caps.
venturisadf also include italic small-caps and
venturisadf offers outline small-caps for certain families.
electrumadf includes oblique small-caps. See the documentation for details.
Disclaimer: I wrote the package support for these fonts though I had nothing to do with the fonts themselves.
Latin Modern includes oblique small-caps as well as the upright variety. I can't remember if
lmodern supports this but
cfr-lm (another disclaimer here) definitely does.
venturisadf supports a number of different fonts arranged into different families so you would not use all of these in the same document - they are just intended to show some of the possibilities. See the documentation for details of what's available and how to access what with package options and extended font selection commands.
cfr-lm oblique small-caps from Latin Modern: