My guess is none of them. I don't feel like any of the four offer the right fit for us. Jeffery isn't the right fit because he's playing on the franchise tag and will cost a lot in terms of compensation. We don't have the resources to pay that compensation after the Goff trade.
Joeckel isn't the right fit because he's injury prone and not effective when healthy. He's struggled with NFL power throughout his career. We already have plenty of depth on the OL. No reason to take him on.
Dee Milliner is highly injury prone and hasn't played well when on the field. We aren't hurting at CB. No reason to take him on.
We already know who Darian Stewart is. He's a replacement-level player. And like the others, he has a long injury history.
If we're going to trade for a player, it needs to be a guy who either offers a short-term fix of a problem or a guy who has long-term appeal. And we should do our best to avoid injury prone players. If I were to offer a short list of guys that I think could fit here (both in terms of being attainable and filling a need), it would be:
1. Pierre Garcon WR Redskins
2. Ronald Leary OG Cowboys
3. T.J. Carrie DB Raiders
4. Crockett Gillmore TE Ravens
5. DeAndre Smelter WR 49ers
Personally, I think the smartest move the Rams could make would be to sign Anquan Boldin. We need a reliable veteran at WR. Boldin would bring leadership and steady play.
However, if they pursued a trade, Garcon also fits that role and Washington could trade him because he's in the final year of his deal and they drafted Josh Doctson in the first round.
Leary makes sense if we're worried about one of our guard spots (Saffold's/Brown's health). He was an above average to good starter on the 2014 Cowboys. La'el Collins took his starting job. The big question would be the cost. He's a free agent at the end of the year so I think Dallas might be willing to deal him.
T.J. Carrie might be available because the Raiders signed Sean Smith and David Amerson played well after the Redskins let him go last year. Carrie has played well throughout his time in Oakland at CB. They needed him to play safety last year due to injuries and he did it decently. He's on a cheap contract and the Raiders might be willing to deal him because they are somewhat deep at CB, signed Reggie Nelson at FS, and drafted Karl Joseph at SS. Carrie would play CB here and allow us to shift LaMarcus Joyner to FS.(an idea that I really like) Plus, he offers additional depth if Gaines is having complications from his foot injury.
I don't know if the Ravens would entertain an offer for Gillmore but I like him. He tore us up last year. He's a do it all type tight end and is still young. They might make him available because Dennis Pitta is supposedly returning from injury.(we'll see) They drafted Maxx Williams in the second round a couple of years ago and signed Ben Watson. If Pitta is back, it might give them enough depth to trade Gillmore who is a solid all-around TE.
I'd be down with trading for Smelter if Chip Kelly isn't high on him. I really liked him in the draft. He redshirted his rookie year after he suffered a torn ACL late in his final year of college. He's a raw kid but is extremely physically talented. I'd definitely take a flier on him if he were cheap to acquire.