I got the LCD Upgrade for my RadExpand 5, which did come with (I think) rubber spacers.
You could just cut up an old inner tube or some neoprene strips from a rubber boot or some such for DIY spacers. If from an inner tube it may require 1 1/2 wraps, maybe 2 to get good compression.
Or use many wraps of cloth-type hockey tape (aka "friction tape"). It's my new favourite secret weapon.
Also, maybe spiral cable wrap, like this stuff, in different colours and diameters:

I'm not absolutely sure if it would be thick enough.
It's also handy (no surprise) for tidying up wiring and brake cable bundles.
You could just cut up an old inner tube or some neoprene strips from a rubber boot or some such for DIY spacers. If from an inner tube it may require 1 1/2 wraps, maybe 2 to get good compression.
Or use many wraps of cloth-type hockey tape (aka "friction tape"). It's my new favourite secret weapon.
Also, maybe spiral cable wrap, like this stuff, in different colours and diameters:

I'm not absolutely sure if it would be thick enough.
It's also handy (no surprise) for tidying up wiring and brake cable bundles.