Hi sam in seattle,
Were you thinking about this as an actual mattress or as a topper for the mattress you have?
If it’s for a mattress then this would be very thin and would be very firm with a significant risk that you would bottom out on the latex. A mattress this thick also wouldn’t have “max softness/cushioning”. Generally the thinnest that would be used for a mattress would be 6".
Wool is a costly material and can add a fair amount to the cost of a latex topper vs latex alone with a stretch knit cover … although it also has some great benefits.
Some of the better options in Seattle (and some will carry latex toppers) are in post #2 here.
There is also a list in post #21 here of the manufacturers that are members of the site (meaning I consider them to be among the best in the country) and sell online and many of these also sell latex toppers (and of course mattresses).
Phoenix