seeking advice on iso pucks /stands or similair that won't stain speakers?

not so much concerned around isolation but rather staining

I've seen finishes stained black instantly by some of these products

I use Isoacoustics pucks under Harbeth 40.3XDs, just checked...no marks after almost 1 year.

Stay away from sorbothane/rubber feet/pods.

Herbie's makes products for that exact purpose - to go between the bottoms of your speakers and the tops of the stands that support them.  They recommend their Fat Dots for the purpose, but their Thin Fat Dots work too if you are not looking for damping, i.e., if you have footers under the stand that take care of damping/isolation.

Stacks Auva's are supposed to be wildly good.

I would think that any plastic type barrier could interact with the footer.  Perhaps a piece of inert paper would work better.