Find and replace groups with symbol— is this even possible?

[KDS4444]

The question may sound straightforward, but hear me out: I have created a series of paths in Illustrator CC to which I have applied a pattern brush stroke of my own design.  Ultimately I need to produce an SVG file out of the image, which means the pattern brush strokes need to go (because otherwise they end up as rasters, which I need to avoid here).  I have converted these brush strokes to a series of regular paths using the "Expand appearance" command.  But the expanded paths are collectively too much! (too much memory: 88,000KB so far).  If I could create a single symbol and use that symbol to replace each of those groups (there are several hundred such groups) I could complete the task at hand instantly...  But I can't seem to identify a way to take a series of identical paths and convert each group into a duplicate of a symbol.  Frankly, I don't think this is even possible to do, but I am hoping I am wrong.  Am I wrong??  I dread the thought of going through my file and identifying each group of expanded paths and replacing it manually with a symbol, but I will do what I have to do.  Unless anyone can show me otherwise. 

[Monika Gause · Accepted solution]

There's a script that does this. You can get it via kelsocartography.com (in the scripts section)

[KDS4444]

Monika— that certainly did the trick!  Took a bit of playing around to get the script installed and working, but ultimately it did the job...

...However, the resulting image, now composed of symbols rather than a patterned stroke, has exploded in size (going from 3,000KB to over 50,000KB), virtually all of which can be accounted for by these new symbols (when I remove them, the file size reverts back to its original small(er) size).  Am now trying to figure out how to make my symbols more efficient— have been trying to create sub-sets of symbols and then replicating those in order to imitate what I had before, but nothing looks as good as what I had with the script you pointed me to.  Any tips on economizing memory when using symbols?  That wasn't my original question, of course, so don't feel obligated to answer it.  But a fifteen-fold increase in memory usage is gonna kill me here!  Gotta find a way to reduce that somehow and still have the image look good in the end somehow...

[Monika Gause]

Did you save it as an AI file?

With PDF compatibility?

Can you try and "save a copy" as SVG (without Illustrator editability), just to see what happens there.