Isolation with levelling


Is it possible to have an isolation base that also allows for levelling i.e. provides both isolation and a level platform for a TT? I have a Scoutmaster and have been looking for a platform that I could put beneath it to adjust for the slight levelling required upon my built-in shelf unit (very stable and sound, but a slight slope that can't be corrected with the supporting cones). Thought further and thought perhaps get one that also offers good isolation. But all of the isolation units I'm checking out assume a level shelf beneath the TT to start.

Am I just missing the units that do indeed offer this?

thanks
terra3
What about a cone which can adjust the level? The Stillpoints cones when used with risers are adjustable.
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stillpoints or the sandbox are good options. also, the bright star air masses level by repositioning the component - I used to use one under my scout. it sounded very good, but only after I mass-loaded the air mass with about 15lbs of lead shot.