The Rush is £360 for frame and forks (although it has track ends, it may not be track geometry, and it may have a few braze-ons) - you said you were looking for a track frame rather than a complete bike. Comes in a range of sizes too, once you worked that one out.....
http://www.mosquito-bikes.co.uk/htdocs/soma.php?name=bikes
The Rush is £360 for frame and forks (although it has track ends, it may not be track geometry, and it may have a few braze-ons) - you said you were looking for a track frame rather than a complete bike. Comes in a range of sizes too, once you worked that one out.....