The retail version of the Marine is in a very similar style to the Soldier. It has the 1960s artwork on the front. On the back of the box, there's a large graphic showing the other figures in the line with the 1960s artwork. Underneath that is the instructions and the 30th anniversary celebration blurb and underneath that is the filecard with the 1960s artwork.
Taking the figure out of the packaging, we can see the Marine in all his details. The helmet is non removable and is dark green with lighter green swirls on it as camo. The face sculpt is a replica of the 1960s facial sculpt, even down to an unpainted scar on his cheek. He's wearing an all green uniform with a dark undershirt. There's brown and black camo all over it. He has a grey webbing belt and pouches. He has black boots on that are covered by his trousers. There are wrinkles and creases in the fabric, that make it look like he's worn this uniform for a while.
The uniform draws inspiration from the above picture, which is of a Marine from 1943 in camo fatigues. Hasbro's own is much darker than that, but it's there.
As with the Solider, there are 2 distinct versions of the filecard, the 1964 artwork one is on the retail release and the Action Figure variant is on the Toys R US Original Action Team 5 pack. Now, the Marine in the TRU version seems to be based on a prototype version, based solely on the brighter colours used and the different colours used on the camo paint scheme.
His accessories include a 4 piece raft, an M1 Garand, backpack and a bazooka in a slightly lighter shade of green than the soldier. The M1 Garand and the Backpack are exactly the same molds and paint. The raft itself is 2 pieces with an oar that slots into the side and has a gun post on the front for attaching the M1 Garand.
Not a bad figure overall and follows on from the WW2 theme from the Action Soldier figure. He can hold his bazooka and sit in his raft as if he's taking part in some nighttime insertion missions in the Pacific Theatre of Operations in the 1940s.
Looking at the 1964 12 Inch Marine, we can see that they have indeed done their best to emulate and recreate the figure in 4 inch scale. While the uniform and and face sculpt are near enough identical, Hasbro didn't give him the parachute, grenades, knife, canteen or M1 carbine, instead choosing to give him a raft.
The Marine fetches around £15 for the single boxed version or £45 for the Original Action Team boxed set with all 5 in. Not a bad figure overall, looks very similar to the Soldier, some people might get some enjoyment out of it with it being a classic figure, however, your mileage may vary