If they are nice clothes, and clothes you really like you might consider taking a few pieces to a seamstress or tailor. Depending on the original cost of the outfits it might be cheaper to have them altered than to buy new. Another option is consignment. If there's a nice consignment store near you take your things in and have them checked out. The split is different everywhere, but the one I worked at back home was 50/50. Then you have a bit of money to spend on new clothes.

Also try eBay. I think my husband said they are doing free listings this week or next. You could put together a few lots with assorted sizes.

Another option is ThredUp.com (http://www.thredup.com/shop/women?&filters[sort]=Featured&filters[size_modifier]=3&). They currently have 64 items in size 4x and 40 items in 5x. I'm not sure how it works exactly, but it might be worth trying.

Also, do you need a lot of professional clothes? You might check out http://intro.gwynniebee.com/ (Gwynnie Bee). This is not a referral link. I have not used the service. I've just seen it on some blogs. They carry mostly dresses, skirts, and slacks. They are like Netflix for plus size clothes! Depending on the plan, you get 1-10 items at a time (ranging from $35 to $159 a month). They pay shipping both ways. And you don't even have to wash them! They launder each article when it comes back!! I don't wear professional clothes, so it wouldn't be worth it to me. But if you have to dress up, you might find this a good deal. Rather than buying clothes you don't expect to wear long.