You're talking about the motor mount perches that weld to the frame, never seen them offered for sale. You'll have to cut some off a junkyard jeep or fab your own.
They make all sorts of V6 and V8 perches for jeeps, probably a reason for that. There are a lot better cheaper engine options than the 4.7L stroker. If you have to have stroker, go GM 383 v8.