Bill,
I can’t speak for the Takumars but I have about a dozen K and M series lenses. Each of the lenses in these series came with a case. Many of the K series lens cases had a “pebbled” texture to the surface of the entire case. I believe this was true of the Takumar cases as well. The lid of each K series case was embossed with SMC Pentax and the focal length and speed of the lens it contained.
The same was true of the M series cases except these, at least the ones I have, all have a smooth leather surface. The case for my K 300 f4 lens is smooth as well so the "pebbled" texture doesn't hold true for all K series cases.
The front lens caps were different for each series as well. The K series caps were slightly more “ornate” and all black with an embossed surface and raised Ashai Pentax.
The SMC K 15 f3.5 and K 17mm f4 fisheye, I believe, were exceptions to this rule and had metal slide on caps.
The M series lens caps featured a smooth surface and a silvered raised Ashai Pentax or just Pentax. The silver, as you can see, tends to wear off over time.
This, of course, doesn’t affect lens performance in any way. However, if you are a collector you might want to have original caps.
Bojidar Dimitrov's Pentax K-Mount Page will provide further details for individual lenses and cases where that information is known.
Welcome to Bojidar Dimitrov's Pentax K-Mount Page
Hope this helps.
Tom G