Helpful advice for WWII USMC(USN) Shadowbox project?

I'm trying to put together a shadowbox for my deceased Stepfather, and am trying to figure out the (historically accurate) items for it. He served from 1944-1947 (USMC) and left the Okinawa battlefield after of a hand grenade wound. While alive, he claimed that no awards were presented to him in person, and our family has jumped through hoops to confirm and obtain documentation. I have received multiple docs from DoD, and each one lists different Medals/Awards. I'm not familiar with some of them, and want to be as close to "accurate" as possible. I have his Purple Heart, but no other awards or decorations. The ones that confuse me are the weapon qual. Badges. His papers list "Rifle Marksman (M1)", "Rifle Sharpshooter", and "Automatic Rifleman". I've searched the internet for these (the SS- Auto. Rifle "clasp" is hard to find). I've seen the badges with a single chain link in the center, 2 chains; Badges with "Marine Corps" in the top bar, and "Sharpshooter" in the top pin bar... seems that they changed over time.
Can anyone give a definitive description of the Badge that would have been issued to a PFC in 1944/45 ? Some VERY LOOSE example picts added here to describe what I'm finding... Thanks.