Hi
I have an RF Generator, Synthesized Wavetek 2520A 2-2200 MHz. It has come in handy for some of my projects and has worked well.
It is not an analyzer like the Sencor you listed but is a nice, general purpose RF generator that will do AM, FM, sweeps etc..
Have a look at the specs. online to see if it will help you. It is fairly heavy so shipping will be cost to consider too.
What sort of FM work are you trying to do? What is your budget for this equipment?