We have two tortoiseshell (calico) cats, both on the larger side (>6 kilos), and we were able to find most everything we need at Qualipet. One warning, though, be prepared for some sticker shock for a large playset/scratching post- I've seen several of the size you're describing at around 200 CHF. Also, we've had some problems with some of the brands of litter tracking about the apartment and we haven't found a brand that we truly like yet.