Am I too late to move my acer tree?

Hi.Welcome to GOY. I would suggest you leave moving it for another month. Then reduce its size by pruning as much of small branches as you can spare. .Prepare planting place in advance adding ericaceous compost to the surrounding soil.. Once transferred stake to ensure it doesn't get wind blown and hope for the best. Good luck.

You could also encourage some fibrous roots to grow closer to the trunk by pushing a spade in around it about 18 inches away in a circle. When you do come to move it the plant shoud have grown a tighter rootball that will transplant more easily. You will need to water and feed it for at least a year after transplanting.