I have been toying with the idea of getting an SDR. Ideally, it would be one that will properly decode LSM/CQPSK transmissions. Which, if any currently available will do that? And, if there are more than one available that will do that, which will decode multiple digital formats? I would love to have a receiver that would receive a given frequency, properly decode it, and also display any other data like PL/DPL/NAC Code/CC/TS/TG ID, etc.
Just as br0adband said, the software is what you are asking about, not the hardware.
The features you are asking for are the result of the software running the SDR, and not tied to any specific SDR hardware. Assuming the SDR will receive the correct frequency range it is the software, the GUI, that will determine what modes can be demodulated/decoded.
From the information you requested it looks like anything from the very cheapest SDR RTL Dongle to the latest wiz-bang wideband SDR will do what you ask, as long as it receives the right frequency range and you can find a software suite that does what you want.
As for the R&S link, sure, you can find it there, for the cost of a nice car on up. By the time all the hardware and software options got added up on the new R&S FSW26 at work it came out to $240k, and it will do everything you asked for

The $13 to $30 RTL SDR option might be the better route for you though.
T!