"Short of installing fences or moving the stuff back to where it was, what can I do to repel deer from the garden?"
Realistically?
(1) You spend all your time in the garden and sleep there. I have better things to do.
(2) Put a dog out by the garden. I like my dogs as pets and indoors, not an animated robot left outside all the time.
(3) Shoot the deer each time you see one in or near the garden. Fish and Game might get a bit persnickety over this, even if you have a nuisance animal permit.
(4) Bite the bullet and put up a fence. This is what I'll be doing this fall and using the tractor to level the perimeter for it. Just remember, a serious deer can jump a 12 foot fence. However, as long as I have a 5 to 6 foot one around the garden, that's enough due diligence to get a permit to shoot any of them that want to play illegal immigrant games in the garden.