Personally, I think it's older than 1950. Values on rolltops depend upon lots of factors. Wood type, condition, size and S or C type of roll to name a few. Obviously, an old walnut or cherry huge fancy antique rolltop in excellent condition would rank the highest value wise. I've seen "new" rolltops and they're easy to spot regarding not being vintage or antique. I could be wrong (wouldn't be the first time) but I think your's is older than 1950. In 1950 rolltops weren't in vogue like they have been in the last 30 or so years...