Some of the fitting manufactureres (Parker, Tompkins, etc) post models on their websites. If you've got a manufacturer and their part number, you might be able to get it directly from them.
You could also try Traceparts.
Hi, I know its a year late but it looks like these people have it in stock - http://www.hydraulicadaptor.com/38-bsp-male-x-916-
Hope it's of help.
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