>>4443458The good Pentax lenses are cheap af. You can get both a 43mm and 77mm for ~$400 each. These are often considered the two best Pentax lenses out there.
What you obviously mean, is that the lenses designed according to MTF and aberration standards compared to contemporary lenses are $$$. But high MTF and aberration correction doesn't mean good unless you're shooting images of test charts.
Where Pentax lenses excel isn't taking perfect pictures of test charts, it's creating aesthetic af images.
Modern lenses from other companies are good at 200% zoom. Pentax lenses are good at "print out a picture of a family that will make the client smile with admiration every time they walk past it" % zoom.
>>4443453Consider K-70, KF, KP, and K3ii, too, which tops out at like $600. They're all still great cameras.