There is now a Freedombone image for the Rock64 single board computer. They're fairly cheap and sufficiently powerful that I've been using one of these as a desktop machine for the last year without any major problems. The Rock64 has an A53 processor which doesn't do speculative execution and so is not vulnerable to an entire category of possible security problems.
There are two images available here. freedombone-main-rock64-arm64.img.xz is the clearnet version and freedombone-onion-rock64-arm64.img.xz is the onion version. It's recommended that you install to an SSD and then connect it to the USB3 port with a USB3 to SATA adapter cable. You will also need to install this boot utility which changes the boot order so that the Rock64 can boot from USB.