Old Beltrame art

We have received a painting from my wife's mother at her death. It was purchased in the early 1950's for around $10,000. Her mother has told her the painting was from approx. 1870's and the Artist only signed at that time with his last name only. "Beltrame" We had the painting professionally cleaned in 2014, and the man that cleaned it said it also looked like something from the late 1800's because of the nails used on the European style stretcher, and the fabric used in the painting. Also he stated the artist was very professional. So basically that is all we know. I will attach a couple photos of the art, and hopefully they will help in the evaluation. The man that cleaned it put paper on the back of the frame now, so will have to remove to take pics of the stretcher, fabric, and the nails, etc. The photo of the painting has been made brighter in Corel Draw so you can see detail, but normally is much darker. The close-up of the signature also shows the fabric quality. If you decide it is worth the time necessary to proceed, I will be willing to either send or take to someone to physically see. The dimentions are approx. 24 1/2" X 48 1/2", would have to take apart to get the exact, also the metric measurements. We would love to sell this painting, so are very interested in the value of course. If needed will try and send more detailed photos if you deem necessary. Thanks, Mel Wade