I definitely think the BC4121-2-0 is a better match than the other models mentioned, Amir.
Looks like they're around 1,500 Euros, new, and I saw dealers selling used horns around 850 Euros. Of course, that would be an overhauled horn. On yours, I don't know if you've got cracks in the wood, you need all new pads and springs, etc.
Jim's right, but I'll turn it around: have an actual oboe player/your instructor play it. If he/she/it/they say it's got problems, then it has problems. The oboe is one of the most difficult instruments to master and neither you nor I are currently qualified to say how good the horn is.
I find it interesting that I didn't see more of these horns being sold in the used market. I don't know if that's because it's a great horn and nobody wants to part with one or because it's junk and was pulled from the market quickly.
As a final thought, there are a couple different fingering systems for the oboe and a couple different octave key mechanisms. I don't know how much of a difference they make in your playing experience, but I'm sure they'd cost more. As an example, I could play a sax without an automatic octave key mechanism, not I wouldn't necessarily want to -- maybe if it was engraved "Adolphe Sax" or something. Your student oboe has a "semi-automatic" octave key. Again, I'm not qualified enough to tell you if that's good or bad.