Depending on the guide's shape etc ...
www.interstateplastics.com will actually do the +1/16 of an inch tolerance cuts in an affordable way. A local machine shop friend recently recommended them to us & our experience with them was great. We had them send us a large quantity of plastic pieces for our transition of updated new controls & $1
coin acceptance ability on 30+ of our Wasco Gen4 washing machines in our laundromat. It allows us to slide out the front panel for easy repair-replace access... something ... that manufacturers sometimes fall short on. The 90% labor factor vs the cost of the part possible consideration!
We have been known to provide a CAD file for outfits including a local plastics fabricator. 3D printing is another option that we have used for more intricate parts. That tends to be more expensive though. It is getting less & less expensive though. It is nice to have the more technologically advanced option to be able to possibly avoid future maintenance by replacing with a material with better attributes than the OEM. Make sure the 3D printer guarantees the cost, quality & turnaround time though!!! Not all futuristic ideas are good but from actual experience 3D Printing is one of the better concepts IMHO that is becoming more & more a reality option for many of us!