I just came across this in amazon. Please could someone suggest me if this is any good: http://www.amazon.com/Luxury-King-Memory-Foam-Mattress/dp/B000KAAV1S/ref=sr_1_2?ie=UTF8&s=home-garden&qid=1256266791&sr=8-2
I do not recommend memory foam. It breaks down too quickly. It's okay as a topper or one thin - 2" or less - layer, but not as a whole mattress. That's my opinion based on experience.
Get yourself any mattress with good springs, as firm as possible. Try it with a latex topper. and/or memory foam topper.
If that doesn't work,cut it open, replace the pu foam with latex, hr foam and/or memory foam like Sensus.
This will work and you can do it for way less than $1000.