You can get a Chinese spindle and VFD kit from BST linear too. As always email directly for a quote, mention this forum.

Steppers, ZappAutomation, Cnc4you, and I think people have used Stepperonline (they advertise on here at least)

Stepper Drivers I got from Zapp, Gary the owner posts on here occasionally with a decent discount code.

KJN also do extrusions.