Drain valve for natural stone washbasin on old workbench

Hello everyone,
I am urgently looking (as an amateur) for a drain valve for a washbasin in my guest bathroom that A) has a thread length of > 130 mm, B) a diameter of 65 mm at the first upper resting ring (i.e. the "counterpart" to the cover), and C) is matte black. I want to install a natural stone washbasin on an old workbench and (above all) have the problem that the bearing edge of the borehole (or whatever you call it) of the washbasin has a 65 mm diameter :oops:
I just can’t find anything. Do you have any tips or ideas on how to proceed?
Thanks in advance, regards![ATTACH alt="IMG_3836.jpg" type="full"]72948[/ATTACH][ATTACH alt="IMG_3838.jpg" type="full"]72949[/ATTACH]

Diameter 63mm is standard, these 2mm are not visible

And Grohe also offers an extension.

Alternatively, make a countersink hole from below into the workbench.