If this does what you're asking for:
[Link: thomasonbbs.com], then it can get got for less than five bucks, apparently even in small quantities.
I had to look that item up. We used to call those equalizers, because they have a response curve that's the inverse of cable. In fact they are not cable simulators at all, but rather inverse response cable equalizers.
If that's not clear yet, signal cable attenuates higher frequencies more than lower frequencies. If you have to run a long bit of cable, then amplify the signal, you want to use one of these doojiggers that has a response complementary to the cable's response... you'll end up with a lower signal level at the end, but flat, if everything matches up.
Of course, there's more to it than that, because of the nature of amplifiers and noise....