Welcome to the forum , Bumbul25 .
I'm really swamped with research projects right now , but I'll suggest that you begin by setting up a free account at : artinfo.com and search through the "L's" in the art prices area of the site ...this can be a bit exhaustive ....but , well ....welcome to my world ...
Sorry I don't recognize the sig , right off the bat .
I can do some snooping around on this one , next week sometime .
2 questions - could you post a pic of the back ? Is the matting on your painting covered by fabric (can't tell from images) ?