I would 3D print (FDM) standoffs in PE with integrated pockets to insert magnets. You can even insert the magnets during the print if you fancy. Though my preference goes to a slide in pocket.

PE sticks to itself and not much else. Packing tape is PE and adhesive. Apply PE tape to the printer bed before printing.

Yeah I have been playing with 3d printing nylon and pps versions because pure pe filament are harder to find. They also often have really really poor layer adhesion and crazy levels of warping.

PPS is not that expensive if you know some of the more specialized filament vendors.

Anyway like I said my use case is weird and may even be transient.

I can think of other use cases, but most are coatings related (Ie using Teflon as a removable masking material, etc).

The removability is actually much less interesting than the ability to strongly bond Teflon.