Originally posted by Qwntm The 70-200 F4 is the tricky one.
How about building a Sony system. The Sony A7RIII would be a little more expensive than the Pentax K1, but you could save money on the new Tamron lenses: 17-28 RXD (or the up coming 20mm f2.8 priced $350), 28-75 RXD and the up coming 70-200 f2.8 for FE mount that'll weight ~ 850gr. That would be a compact kit. Now if you go the DSLR route and Tmaron, you could still get a D810 with the 17-35 f4 Tamron, 24-70 Tamron and 70-210 f4 Tamron.
---------- Post added 24-10-19 at 16:34 ----------
(*) The DA 12-24 is a crop lens, not great on the K1, heavy vignetting, uncontrolled edge perf at wide). The FA 70-210, well that's a possibility for the compact landscape tele, cheap, light weight, but it's a old lens, not up to the today's standards of the other new lenses you could get from evenTamron or Sigma.