Unknown purpose STERLING item. 204534 ADAPTOR

[reccetrooper]

Does anyone know what this is?

Purchased recently and still sealed, it was carefully unwrapped today to examine it and take photos. The label says 204534 Adaptor - 1

It’s a 1959 Fazakerley made Sterling L1A2 magazine body, completely stripped of parts, on the base is welded a pintle that has been turned from square bar stock, you can see the marks left by the four-jaw chuck. The whole is finished in suncorite.