After not being able to find an intact rear bumper for my 91 wagon**, i bought a rear bumper (aka ..bumper..cover) for a hatchback to modify for the wagon. i had to do two things to it, one was to use a saber saw to cut away the upper surface for the gate to swing by....and I ran the saber saw at a low speed to avoid cracking the plastic of the bumper. The other mod was to use longer studs to mount it to the wagon body. The original studs were not too hard to get out, by drilling through a pair of pop rivets on each side. i got longer metric bolts from a hardware store and brazed them onto the mounting strip the original studs were attached to. This is only needed for the wagon body, since its body has a thicker rear mounting surface, likely due to the large rear opening the wagon has. It looks good from ten feet back.
I needed a new front bumper cover for one of my 2nd gen escorts, but am still looking, mostly on ebay. Meanwhile I am using a homemade bumper featuring a chunk of 2" by 10" painted gloss black.
**My personal experience is that any escort bumper in a junkyard is either already badly cracked or pretty thoroughly smashed.