It will depend on individual player, I would choose one that isn't totally skewed for defense, but that's me, I like my wing backs to think about starting attacks.

His morale might suffer a bit, but that will also vary depending on how well he likes being OOP. I have gotten consistent 7's on a guy OOP, so I would say give it a try, since you really don't have a choice right now, but start looking for a DR in a week or so when bidding wars slow down.

Also consider your 3*, does he get good ratings? 8's? If so I would play him even if only 3*.