I am looking for a vendor that can do custom decals for a RC airplane. Don't want to wait 5 weeks. Wondering if anyone has a reliable vendor. All ideas have been done in photoshop and are easy to read. Example is attached.

Have you tried Callie's Graphics? https://callie-graphics.com
Oh crap sorry I see she is quoting 5weeks on custom orders!!!!!!!

Callie has that much of a waiting list because the product is good. That being said you might try your local vinyl sign company. It probably wouldn't work out if looking for something as large as the attached example but I have had good luck with making waterslide decals up to four inches tall.