Rainbo in Santa Monica does very good work.
www.rainborecords.com
If you're using United, I'd recommend getting your records mastered elsewhere and having the masters sent to United - their mastering department was very shoddy when I was using them some years ago.
Shipping will be a significant factor in the cost, so united may wind up being much cheaper for the Midwest and East.
Also, 10"s generally cost more than 12"s, so unless you plan on shipping a lot of them overseas, you may want to just do it on 12". You can do like Sven-Erik Geddes did with the Shatners' record and use the extra space for something nutty.