Lee Reynolds Painting

The painting is signed Lee Reynolds and there are numbers on the back, 4-108189, 180-51369-9, 9335-11 and the words Market Day.  There is no stamp to indicate vanguard studios as I am aware there were a large number of paintings done by Vangaard studios under the name Lee Reynolds, that were not painted by Lee Reynolds (Burr), but by staff artists.  I understand Mr Burr painted a number of paintings under the name of Lee Reynolds, but has stated he painted no more than a few dozen such paintings.  I'm trying to find out if this is an original painted by Lee Reynolds Burr or if there is a way to tell.  Also, what would be the approximate asking price should I decide to sell it?  Thanks for sharing your time and talent with a non-artist type.