Using other Themes "Toolbar" icons Actions

[Solar]

Hey guys!!

I was wondering (i'm sure it is) but how to use other Theme Icons for Toolbar Actions? Let's say I myself is using as default the RADO them (latest version how it was cuztomized by Nick). But I sometimes find myself while creating my Own Toolbars, that i'm out of "icons" to associate with my Actions, so was wondering how to get other Themes like REACTION icons and use them?

Any little step input on how to achieve this would be much then appreciated!

Thank you and wish you ALL a marvelous amazing and Healthy Week

Cheers!