EDIT Thanks everybody! I got it done same day with somebody, opted to screw my own holes, and it worked great. So great that I'm thinking to let the whole thing where I needed the piece to be done by 3D print. (It extension for a insert of a panel of pet door, I attach the picture in the comments, maybe it's useful for somebody)
I need a piece of white plastic 20mm x 100mm x 294mm.
Just got an idea from internet that could be 3D printed maybe and that some libraries provide that, but not Carlow.
Any idea where this can be done?
And also, can 3D printed piece can be screwed into?