Century is importing the MKE made H&K clones, allegedly still made on the German tools and patterns just like H&K did in the '60s. The 40 and 10mm MP5 didn't exist until the '90s, so you probably won't see one from MKE/Century.
Now that Zenith and PTR are making their own, if someone were to add a caliber I'd expect it to be one of them. PSA's vaporware might surprises us one day.
Even H&K discontinued the real MP5/40 and MP5/10 in the early '00s though, so don't hold your breath.