For the proposed Na level, there would be no problem what so ever if you decided to use table salt to boost the Cl level. If anything, the overall sweetness perception of the beer could improve with the salt addition.
I add table salt to almost all my brewing water for flavor impacts. The Na level I use is typically at your proposed level or less, though. So I'm not pushing at all.
I suggest that you don't need to worry about Na at levels of 50 ppm or less in almost any beer. Above that level, you should raise an eyebrow. However, Na can be an asset in roastier beers since I find that it improves and mellows the flavors. I wouldn't go over 100 ppm Na, since the flavor is just starting to become apparent at that level. At 250 ppm Na, anyone would recognize a salty flavor.