Seems like. It's a fairly practical model for a lot of simpler devices. I've seen dedicated mouse controllers along similar lines. Microchip themselves produce a number of devices that I'm sure are PIC-based internally too.
I don't think I've seen a sheet on any sort of audio generator that has a sample file. Normally, you'll buy or request a couple samples to use in prototyping. There are way too many factors that affect what it'll sound like to make a sample file non-useful.