Based on the dimensions you listed, I'm pretty sure that is an RF-30/31. If I had to guess, based on color, it is a Taiwanese Enco model. Every single Taiwanese RF I've ever seen has that "Warning" label at the front of the head in red, and the shape of that black plastic front cover is classic Rong Fu. The shape of the knobs on the downfeed is also typical RF. I also suspect it is a relatively late model based on the shape of the top cover; I'm going to guess this was made sometime after the year 2000.
Looks like it needs a good cleaning but they are reliable, solid machines. Should serve you well.