Regarding the M16, there are not very many of them around so it’s unlikely that you will find one in the US.
I have actually stopped making most of the TFPRO range now, just building a few compressors and fixing one or two elderly JoeMeek pieces…. I’m trying hard to slow down! (dont forget, I’m very old!)
I do have one last M16 that I use in my own studio and that one is available, but I really think that will be the last one.