Hi,
The 900' distance limitation is end-to-end. (It's actually something like 12dB end-to-end loss rather than an actual distance.) Don't forget, because you have equal level point at the DSX you only need to consider the distance from the 10008 to the DSX. (Assuming that you're connecting to a DSX)
I've haven't heard about any "low-loss" co-ax cable that allows the distance to be extended but it's been a long time since I worked in this kind of environment, so you never know. Typically, the best you can do is 450' using 728A co-ax (735A co-ax will only go 225') so if you need to extend you're really looking at line-extenders or repeaters.
HTH
Andrew.