I have currently a 10-year-old IKEA Sultan 160x200 12cm latex mattress, which is pretty hard, ikea does not manufacture them anymore, very happy with it. Originally it costed 239 CHF.

I looked in the internet but I found such latex mattresses only at prices about 1600/CHF which seems to me like a fortune for a mattress.

have you any idea where (around Luzern/Zug) I can find similar latex mattresses but not at insane prices? I like the latex one because they are hard and you don't sink in them when you sit on the edge of the bed.

Well ikea has one, but for 699. Their mattresses seem to have gone up a lot in price over the years.

the one that ikea has now is not so hard and it is higher
also the quality of this one is worse than 10 years ago