Resources for CBeam Router
CBeam Kit
Available from OpenBuilds. Numerous options available. Look at the WorkBee and LEAD bundles for larger footprint machines. Also, similar machines can be found on eBay/Amazon/Ali.
Teensy Breakout Board
Available from Brookwood Design on Tindie. Uses a Teensy 4.1 from PJRC.com. Some assembly required.
Stepper Motors
NEMA23 Motors. 175 Ounce/Inch Torque. Higher would be OK. Widely available on eBay/Amazon/Ali.
Stepper Drivers
TB6600. I bought these a while ago and they don't seem to be available any more. The newer style will work - DM542 (or clones) will work. There are many other less expensive drivers that will work as well. I have the motor current set for 2.0A but select a driver that supports 2.5A at minimum. Widely available on eBay/Amazon/Ali.
Also note, you will see TB6600 drivers available on eBay/Amazon/Ali but be aware these are almost all fakes and don't use the TB6600 chip. You can tell because they claim to have 1/32 microstepping which the TB6600 does not have.
Power Supplies
24VDC 14.6A Power supply - Meanwell LRS-350-24. Widely available. 24VDC to 12VDC stepdown converter for relays and 0-10V output. This has a handy display for adjustment.
CNC Software
grblHAL running on the Teensy 4.1. Open Source. Uses IOSender on a PC. Also Open Source.