You can buy frozen shao lung bao from many Chinese supermarkets and some Chinese restaurants in OC. Quality varies and you'd have to experiment a bit with your steamer to find something you like. Many of these in plain packaging came from folks who made them at home for extra $$. I'll dig around and see if anyone knows a good place in OC.
You could also try J & J in San Gabriel:
J & J Restaurant
301 W Valley Blvd
San Gabriel, CA 91776
(626) 308-9238
<a href="http://www.yelp.com/biz/j-and-j-restaurant-san-gabriel">http://www.yelp.com/biz/j-and-j-restaurant-san-gabriel</a>
<img src="http://static.px.yelp.com/bphoto/UU705TyE7yG9CHK5r3_Yug/l" alt="" />
<img src="http://static.px.yelp.com/bphoto/xoZGjOoFsdj6Oh2l_h7yUQ/l" alt="" />
<img src="http://static.px.yelp.com/bphoto/x3R5irtAKvxx8ct-9BS-zQ/l" alt="" />
<img src="http://static.px.yelp.com/bphoto/5nPET2bseqdkD6KUeq3JpA/l" alt="" />
<img src="http://static.px.yelp.com/bphoto/daSBAKTJ1Bbg-q8wxw5wSQ/l" alt="" />
Get the regular and crab meat shao lung bao here. Cheaper than Ding Tai Feng and closer than Nanxiang Dumpling House in Shangai.
<a href="http://edition.cnn.com/2006/WORLD/asiapcf/04/04/lustout.shanghai3/index.html">http://edition.cnn.com/2006/WORLD/asiapcf/04/04/lustout.shanghai3/index.html</a>
<a href="http://www.professionaltravelguide.com/shanghai/dining/local-regional/nanxiang-dumpling-house-478182/">http://www.professionaltravelguide.com/shanghai/dining/local-regional/nanxiang-dumpling-house-478182/</a>
<img src="http://d3.biggestmenu.com/00/00/28/1500b8db170821c2_m.jpg" alt="" />