I read that LIMA is in financial trouble and that they stopped production. But perhaps you find an older TGV model on eBay to cannibalize for getting the missing parts.
The problem is, that there are several generations of the TGV models which are quite different both internally and detailwise. (LIMA evolved from cheap toy production to quite beautiful RR models.) Your TGV (from 15 years ago) is probably from of the first or perhaps second production run, so it might be difficult to find fitting replacement parts.
Here in Europe I never saw a dress-up kit for LIMA locomotives. As Russ said, in Europe you hardly find superdetailing parts. There were a few little firms in Germany which offered some parts (and complete kits) - but only for steam engines and perhaps one pantograph or another for electric locos.
Ron