Hello Howard, welcome to the Forum!
There's quite a few here who shoot film as well as digital, in my case only a couple rolls a month, but hundreds of digital clicks. Thanks to the enduring K-mount we have that option.
The K-x would be a good choice for an entry body, but I'll add another suggestion for you to consider; The K10D.
https://www.pentaxforums.com/forums/6-pentax-dslr-discussion/242738-k10d-club-36.html
Compared to the K-x, you'll give up 2MP, HDR, Video, LV and in-camera AA-power (but that is available with the BG2 grip) plus, the K10D is not nearly as good at high-ISO, either. The real-world max ISO is about 400; Seriously.
But it also has a different type of sensor, the CCD, which renders colors, tones and sharpness levels in a way many describe as 'film-like', and it's just as true for B+W as color renditions.
Granted, that's hardly an unbiased opinion. Check out the photos on the thread and see for yourself.
Good luck!
Ron