bll 2018-8-8: I have created a localized, scalable spinbox widget. It should be compatible with a ttk::spinbox. Released under the zlib/libpng license as always.
The source can be found here: https://sourceforge.net/p/tcl-lspinbox/code/ci/default/tree/
The required packages 'repeatbutton' and 'colorutils' are included in the repo.
The locale command can be found here: https://sourceforge.net/projects/tcl-collate/files/
See also: locale package