tommac:
I can state the obvious; you have a seriously used R35 of late production. (REF: Thread, "Mle1886-M93-R35" below and near the bottom of the first page of this thread-index.) In 1939, and perhaps until the Armistice, the side-bar sling mount began to appear. Whether they were all assembled in this manner, or concurrent with the sling swivel model is unknown. Identical in all other regards the two types have been designated, at least in this country , as the cavalry and infantry models, respectively. Most are found in remarkably well preserved condition, having gone to fortress garrisons or ancillary troops. Does the new butt-stock serial number match the bolt? If it does, it will have an anomaly similar to another such carbine which lacked the Crakow mark. (If you do not know that already, the German forum can confirm it for you.) The mark is encountered upon occasion, and in that location, but others are the experts.
There is both photographic, and graphic prose, that could place your carbine in the most intrepid of circumstances, and provide for its convoluted journeys. The only value in that would be a rollicking tale best told in the fire's dim, with sabers reflecting light from the wall. Its true value looks to be a little more than its parts. But oh, the fetish value will depend only upon the afore mentioned circumstantial documentation, and the owner's abilities as a raconteur.
There is no denying that it lends itself to speculation. Import or souvenir, I have never seen an R35 that was import marked. So, as I have told more than one potential customer who has inquired as to the 'history' of such firearms, and was not content with a recounting of known production and probable issuance: 'it is not import marked, so feel free to make up your own story'.
However, so as not to leave you with the impression that this response is completely dismissive - look to the Medjerda valley of mid-November, 1942. There is potential for the kind of hack article that brings attention, to the detriment of technical works. The outline came Athena like, fully formed, when I first saw your carbine.