A couple of the OOP WHFB Empire Greatswords had them, as did
Mordheim accessories sprure. Not the cheapest option, but they will probably crop up on eBay.
Because of this you can find a number of 3d printable files with them available currently, if that takes your fancy.
Would be useful to give specific options, so I'm going to point to the work of two french sculptors I really like.
the set includes bodies with integrated arms holding flamberge, separate arms that link up with flamberge hands and entirely separate flamberges as well, plus a bunch more.