Looks like the EB-85 (no attached antenna) is a drop in replacement for the ET-312 with lower power consumption and 5Hz output. I would love to order these from sparkfun (since you already carry Etek products). It also has a wider power supply range (3.3-5v). This could be a good GPS module to offer, and etek has informed me that they have no US distributor for the antenna-less version.
http://www.etek.com.tw/product_detail_114.htm
Thanks,
Scott