These were near final prototypes that were field trialed near the end of WWII. The exact numbers produced is unknown, but relatively few as far as gun numbers are concerned. Beyond the very positive reports, feedback concerning the particulars allowed the production version in 1949 to be arrived at. So, in a nutshell, no, these were not exactly the the same SKSs that we use.
On thing that came up during the SKS development is the use of detachable magazines. It was originally intended to have one, but Stalin nixed the idea, as he feared that soldiers would lose them and generally cost a lot of money to keep supplied. So Simonov complied by substituting in a fixed magazine and the stripper clips for quick reloading. The expense of lost strippers was negligible and well known, so Stalin was OK with that. That little bit of history may well have something to do with why current SKSs can be converted to accept detachable magazines today!