I converted a owb holster for the 5.7 mrd (mk3) to an iwb holster which is pretty concealable! : r/FNHerstal
FN 5.7 MK2 IWB Hinge Holster Package Deal
Fobus FNH Evolution Holster pour FN Five-Seven (sauf IOM et MK2), pagaie Droite Noir : Amazon.fr: Sports et Loisirs
EA Red River Tactical Type I Holster V3 Five Seven MKII or MKIII MRD V3 OWB 0.125" Kydex Holster Black
Amazon.com: Neptune Concealment Kydex Holster for FN 5.7 Gen 1 & 2 - Light/Laser Bearing Nestor Series IWB or OWB - Veteran Made in USA : Handmade Products