Best of luck with obtaining an 0 exp Gwen for 350. Her price tag usually runs over a 100 clintz on the market and for good reason. You might also want to specify that you want a Gwen with ZERO exp rather than a Lvl 1. Otherwise, you might trade for a Gwen (Lvl1) that's a game away from leveling up.
Friday you should be able to buy a Ella for under 200 clintz.