Be interesting attempting to mount the K-1 on it!

Yes, on full frame, those were the typical lenses in the film days which is when they date from. Pentax's dedicated portrait lens was the 85mm soft focus. Crop sensors need perhaps a little less, 50-70mm is fine for APS-C. At the end of the day it depends on how much room you have as in a small room you may not be able to get far enough away with the longer focal lengths.
As for macro work, around 100mm is fine as it allows keeping a reasonable distance from the miniature subject. 35mm is really too close for that, though OK for flowers which don't take fright easily!

The 50mm lens could be used for portraits, but probably not at 1:1 unless the portraits are of ants and flies etc. as 1:1 macro happens to be a very close focussing facility. The 35mm Limited is also a 1:1 macro lens.
If you already have an 18-55mm zoom you can get some idea from that as to what the prime lenses will give you at their respective focal lengths. In fact an 18-55 might well suffice for your (people) portraits.
The 35 & 50mm macros allow focusing much closer than the standard zoom which is useful if your subjects are small insects and maybe stamps and coins where the standard zoom cannot focus close enough. They focus to infinity too!
Both the 35mm ltd & 50mm macro are very sharp lenses. The 50mm macro is full frame and APS-C compatible, The 35mm Ltd is just APS-C (it vignettes on full frame.)
I don't know what lenses you have but worth considering is the newish Pentax 16-85mm or 18-135mm if you are in the market for a new lens. The Sigma 17-70 isn't a true macro, it just focuses fairly close, but what you describe as a requirement for portraits it doesn't sound like you really need a macro lens at all. By the way, Pentax make a 17-70mm too.
Have a look a https://en.wikipedia.org/wiki/Macro_photography to find out what macro lenses are for and see if they are what you really would like.

Where did you purchase your K50 from? Some Pentax dealers offer a two year guarantee which should cover it at a year and a half. But didn't you add it now works fine which might prove hard proving a fault?

Is it full of gold sovereigns?

Go on, you know you want to!

That's good to know. In those days asking them to stop had no effect.

They learnt from that and it should now be protected against it. At least that's what our National Grid claim.
http://nationalgridconnecting.com/storm-in-a-teacup/

Do Serif still spam you with phone calls and emails. That was the worst part of obtaining their products! Endless calls and emails when a new version came out or a new product they'd bought in and try and sell it to you.