Those images of HUDs (except for the latter) are mockups made by stitching together leftover graphics, since these HUDs were never implemented in the game's code (however the feature for unique HUDs still exists and is used for switching between on-foot and MCA HUDs)
Main Menu, left sideMain Menu, left side without background (presumably was supposed to be used when the game is paused)UCA logo, part of the left sideMain Menu, right side, bigRender of Admiral Akkaraju, part of the big right sideMain Menu, top-right sideMain Menu, bottom-right sideMonolith Productions logo, part of the bottom-right side