You will be very VERY lucky to find one of them anywhere, as they are rare, almost unobtainium, as is most metal cone types, they are out there, but good ones are hard to get.
On the other hand, you can covert to an all glass type 16CP4(A), of which ETF has 4, it seems, it should not be too hard to convert over.
https://docs.google.com/spreadsheets...18&single=true