Hi tsunamis,
There is a little more about the Tempurpedic weightless mattresses in post #2 here and in post #2 here.
Select foam makes two mattresses here that are designed to be similar to the two Tempurpedic Weightless models. NOTE ADDED: Because of ongoing customer service issues and delays Select Foam’s membership has been terminated and I would read the warning here before considering them.
The Tempflow Flexia here is also designed to be similar to the Tempurpedic Weightless Supreme.
Pure Crafted Beds also has their True Essence mattress which has 2.25" of memory foam over a more resilient polyfoam transition layer and may be somewhat similar as well and may also be worth talking to.
There may also be other local mattresses available that also have a similar design (a thinner layer of memory foam over a more resilient polyfoam or latex transition layer) and may also feel similar but you would need to test these in person to see how close they feel to you.
Phoenix