I have now seen an image of the weight in question. It is not one that I had seen before amongst the various modern Baccarat output.
To be honest, in my view it's also not as nice as the usual modern French ones - but that's just personal taste.
As for how much to sell for ... why not just put a reserve of what you paid plus a bit for good measure. That will be a profit. Let the bidders decide the current "market value". Or if maximum profit is the motive, just put a really high reserve on it and see how close it gets.
Or, as I suggested earlier, contact a regular paperweight dealer and ask them.