Update:

> NEXCOM has introduced its first T4240-based hardware but still no sign of the T4240RDB.

"T4240RDB: 1U, available Q3-13, Nexcom"
http://www.youtube.com/watch?v=U3cSmYV1mJ8

In the same video, the narrator says about the T4240RDB in comparison to the T4240QDS:

"We are working with partner Nexcom in development of a 1U reference design that brings out most of the same functionality in a much smaller form factor at less than half the cost, which will be available in Q3-13."

This means the "low cost" T4240RDB will be below 2000 USD.