Suitable GPS module

Hi
First of all i am new to this forum, and i don't hope i break any rules written or unwritten with this question.

I need a GPS module for a GPS "Vehicle-tracker" im making.
The size of the whole tracker cannot exceed 1.9cm diameter (0.75") and 15cm lenght (5.9"), shape is cylendrical.

I found a module, but it is unfortunatly pretty expensive:
SparkFun Electronics - GPS Micro-Mini

So i am looking for something like the above, but cheaper.
Any ideas?

**broken link removed**

You can go a lot longer than 15 cm in the seat tube of a bike.