These guys offer an option…
https://soundocity.com/shop/outriggers/low-profile-caster-outriggers/
If you know any metal workers they may be able to help out with some 2” flat stock being bent at designated points to be outriggers that accept office chair casters made like roller blade wheels for hardwood floor. I had a set made a while ago for a pair of Eggleston Andra that needed to move back when not in use. The flat stock was measured to clear the bottom of the Andra, bent up at 45 degrees and back out again at a height that allowed the caster to have the speaker sit at the same height as they did on spikes. Roughly 1.5” off the ground. They drilled the outrigger at I believe 5/16” to accept the post of the chair casters. Worked really well and looked very nice once painted black.
https://soundocity.com/shop/outriggers/low-profile-caster-outriggers/
If you know any metal workers they may be able to help out with some 2” flat stock being bent at designated points to be outriggers that accept office chair casters made like roller blade wheels for hardwood floor. I had a set made a while ago for a pair of Eggleston Andra that needed to move back when not in use. The flat stock was measured to clear the bottom of the Andra, bent up at 45 degrees and back out again at a height that allowed the caster to have the speaker sit at the same height as they did on spikes. Roughly 1.5” off the ground. They drilled the outrigger at I believe 5/16” to accept the post of the chair casters. Worked really well and looked very nice once painted black.