Old Italian Violin Dominicus Montagnana

This is an old italian violin with the label Dominicus Montagnana.  I know the real deal for these violins are few and far between so i am not expecting to be sitting on a small fortune (though that would be nice!).

I am mainly curious on the approximate value and date of the violin, as well as any other history that can be provided. 

This is what i know about my violin:

My father purchased this violin in 1993 from a woman in her mid 60s to early 70s currently living in Indiana.  She was a career violinist who grew up and played professionally in Chicago until she got arthritis in her 50s (i think possibly her 40s).  This ended her career.  She sold the violin to my dad for the same price her father had bought if for during the Great Depression.  (apprx. $2,000-$2,500).  She wasnt interested in the money aspect, she just wanted the violin to be played, not sold in an estate sale or rotting away in a closet.  She had been hanging on to it for sentimental reasons and had no children to pass it to (or none that played maybe?) 

So this would had made this a professional level violin and probably pretty expensive if it sold for that high during the Great Depression.  She was a career violinist in Chicago and she was from a family with enough money to afford the luxury of such a fine instrument during the great depression, so i'm assuming this violin has some value based just on that alone.

The History that was told to us when we purchased the violin:

The violin is Italian made and was imported from Italy during the Great Depression to Chicago.  She told us when she purchased it that it was made in the 1700s.  The year that she told us was on the certificate was 1735.  However, I am not sure if this is something that she knew or just believed to be true.  Perhaps she had learned this through a previous appraisal?  She did live most of her life in Chicago and her family did have the financial means to have an instrument appraised so this is possible.  However, I never saw any documentation personally and nowhere inside the violin do i see a clear date written, just the number 17.

Beyond that, it does have many features that common to old italian violins, similar varnish, the nails were used in attaching the back, the wood, the body style fits the time period (as far as i can tell- i actually have no idea really what i'm talking about other than just by looking at other pics of other old italian violins from this period)  I do believe that this violin is definately a beautiful instrument.  Possibly a lost gem.  Any information that anyone has on it would be greatly appreciated!!!

If any addition pics are needed or measurements, feel free to ask and i will get them posted.  i do not plan to sell this violin at this time, unless it is worth quite a bit.  If that is the case, i will consider selling it to repay the much owed debt to my father and mother for always supporting me and my music.