This is a type of query that crops up from time to time and the best answer is, "How much do you want to spend?"
I am sure some custom shop would be willing to tackle the job of cutting the frame in half and welding in an extender to lengthen the magazine well, making a new magazine from scratch, making or extending the sear bar, extending the slide as well as converting it to rimfire, etc. And the job would cost at least $2500. So it is not always easy to say something will be impossible if enough money is involved. But it is sure as heck not feasible or reasonable.