I did something similiar a few years ago, and I found that 2 old flatbed scanners made a nice table - and I got them for free for the asking.
once you remove the stuff you dont need, you get steppers and the gearing.
I got X/Y by putting one on top of the other, and used the glass from one to make the platform.
I never completed it though, as a house move meant I had to trim down my junk collection :-(
As a result I didnt get to finish the pen holder but the few tests I did went ok.
Video is shaky and may cause boredom/seizures, but included to show what I used. I also didnt use arduino back then as I had not discovered its many joys.https://www.youtube.com/watch?v=XBEq7lnMjfo
might inspire you, might scare you :-)