Lisa that is a very good question. I would like to know where to find them as well. (with pigtails)
This gal on ebay has lots of wigs, just gave the link so you can look at her other items and she is very nice to deal with too.
http://cgi.ebay.com/MEI-Pony-Tail-Wig-S … 48378a9ef3
Haven’t actually looked but you might try looking for human wigs Hopefully someone else will be able to help you find what your looking for.
Babies by Bernadette on ebay sells some larger wigs.
She says this one will fit Iris:
http://cgi.ebay.com/LIBBY-Wig-Size-17-5 … 35a4f8a957
And so does Dolls by Sandie:
http://www.dollsbysandie.com/index.php? … _list&c=42
Here’s one but it does have little piggies:
http://audreysdolls.com/item.cfm?itemID … atalogID=5