Pappa scored 26 goals and had 16 assists from 2009-12 before moving to Dutch side Heerenveen midway through the 2012 season. But he only played 283 minutes over parts of two seasons before the two sides agreed to terminate the contract.
Whether or not to pick Pappa is not just about how the Sounders value that specific player, though. If the Sounders would rather have Erik Friberg, for instance, they'll obviously want to wait until that situation is resolved before making a decision. Assuming the rumors are true that Bologna are interested in Friberg, the Sounders would probably need to wait until the Italian transfer window is closed.
Coincidentally, that's a few hours before the MLS deadline. Unfortunately, that's about two hours after the Allocation window closes.
There's also the possibility that the Sounders would pick Pappa and then attempt to trade him. The Chicago Fire are the only other team that have openly expressed interest in Pappa -- and that's also where he apparently wants to play -- but they are all the way down at No. 7 in the Allocation Ranking.
Among the players that might be of interest to the Sounders are Dilly Duka and Patrick Nyarko. Duka has long been a player with tons of talent, but not necessarily the production you'd like to see. He is coming off a career best four-goal and three-assist season, though, and plays primarily on the left. Nyarko has 10 goals and 30 assists over the past four seasons, but plays on the right side and is probably not someone the Fire are looking to trade.
In any case, this should all be settled by sometime Friday afternoon.