audiscape pods are expensive (£200+)
i have some custom ones which are made from half original door pocket (the long pocket section) bonded to a speaker pod made from MDF, finished with fibreglass and painted black so it all blends in and looks original

this was a test fit, what it doesnt show is that you need to cut a big hole into the door card immediately behind the speaker pod and stick dynamat on the rear of the door cards and the inside of the door skin/panel. this help the door act like a speaker box rather than just the pod, and dynamat stops everything rattling