If you have a shoulder harness like the ones we used to use for an Uzi, then the Raider is "concealable" (laughs politely).
It is smaller than a MK17 Banshee (AR pistol; uses P320 mags) for sure, but it is bulky. Ben Griffith (and I, and others) have chopped the sight bridge off the Raider and use slide mounted RDS and TLR-7s to keep the size down.
While the holster for the Raider X is on the drawing board, there's not a release date yet. Many carry it in a sling bag or on a bungee sling.
The Raider for the 365 is capable of being carried IWB / Appendix carry. Plenty of video to support that - or it was released with a holster available that takes standard Safariland bits for belt/drop rig carry.