I think the Bakti and Chernobyl keep spots are still open. From my understanding, Mohki keep is under contract and North Point keep is not for sale. I would definitely advise talking to RPK leadership if you're planning on building any keep in Myrland.
Unfortunately, all the previous Myrland keep owners (with exception to nWo and FarmersMarket) were involved in the most recent Muppet Alliance against RPK and there was a natural reckoning. From my understanding, all of the Sarducaa keeps with the exception of Monk are all part of one Sarducaa alliance.