I'm sure Keith will chime in, but the basic helmet looks to be a "Team Wendy" specifically the EXFIL SAR Backcountry model with rails. The conversion to flight helmet is probably from Sky Cowboy Supply Company. They have various ways to convert helmets including individual parts or a DIY version or a complete flight helmet with visor and/or headset.

I can vouch for the comfort of the Team Wendy Helmet.

Dave.

https://www.teamwendy.com/search-rescue

https://www.skycowboysupplyco.com/shop-1