16 pounds of Bakelite for $2

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I won a mystery box lot of handsets, caps, and transmitters in an on-line auction for the minimum $2 bid.  Shipping and handling in a 12X12X12 sixteen pound box added another $20.57=$22.97.  I made a bid hoping to purchase for the large number of WE F1 handset caps (40 or so--not shown) and the banded and molded AE caps for type 40 handsets I need for project phones.  Other items are several red painted plastics, a broken dial blank, a large brass microphone transmitter with a side push to talk button, an E1 receiver element/cap, a type 38 handset with epoxy on the spit cup and an extra earpiece, what I think is a Leich F1-type handset missing its vented spitcup insert.  Also found two groups of items that have me a little puzzled. First, there is a large collection of what I think are receiver caps from PAX type handsets used in AE32 and AE33 phones.  It looks to me like these phones maybe used 38 type handsets but I am unsure what element is used under this cap. They fit type 38 thread and do not fit type 40 handsets and are marked AE inside. Kind of an unusual part to have so many of for an uncommon style phone.  
Discussed here: AE32

Second, there is a  number of large faced transmitters with brass faceplates and Bakelite and plastic sealed backs using rear bolts into the faceplate. All are marked 647a, all have rear terminal bolts, and most have metal brackets on the back. My best bet is that these are for some sort of panel or box phone or intercom.  I have been unable to find anything except one post guessing these are WE, which I don't think is correct:
647a Transmitter