Hello,
You should check around where you live for graphic shops or sign shops. We have several graphic and sign shops around here and they offer custom graphics and vinyl work. They can take an image provided by you and print that to vinyl lettering, cut it and then install it for you.
If you want to see one thats online, you could check
here.
You could also consider a
mural.
For original decals, the only place I know to get them would from Forest River. I dont know if you could order them, maybe check their website or call them, but if not you could always check with a local RV dealer. If your camper is still in production, they can likely order decals for it.