BairdMaritime provides information on a new Offshore Patrol Vessel (OPV) built in Vietnam for the Vietnam Marine Police (soon to be Vietnam Coast Guard) to a Damen design, that looks a whole lot like an Offshore Patrol Cutter (OPC). There is also information in the article about their developing relationship with the USCG.
She is reported to be 2500 tons, 90 meters (295′) in length, 14 meters (46′) of beam, 21 knots, with a crew of 70.
I think the Bollinger candidate for the OPC may be similar. This is apparently based on the Damen OPV2400. The OPC candidate is probably based on the slightly larger OPV2600 since it will probably need additional volume for fuel to provide the range the USCG requires, a couple of hundred tons heavier, 8 meters (26′) longer, and two or three knots faster because of its greater length (same horsepower).
More information about Damen designs for OPVs can be seen via the link below: