For any items shown with a price, but no 'Add to Cart' option, I suggest emailing a list to playmobil customer services in your country and asking if any of them can be supplied. That may also work for figures and parts from recent sets declared to be no longer available. You must give the 8-digit part numbers (look up on PlaymoDB or, for more recent sets, look up in instructions (bauanleitung) on playmobil website). On a good day, customer services may be able to find alternative part numbers for discontinued parts (or you might find them on PlaymoDB). You may be out of luck if you want Klingons or figures from other licensed sets.
Last time I did this, a couple of months ago, I was able to get all but one of about 15 items.