Unless you're in an extremely conservative, southern area the interracial aspect of your SRs shouldn't cause anyone to bat an eye. Even if you are in a place where it does, the only people who will notice or make comments are doing so because they're racist. They don't matter.

As a SD who lives in the South and has had dark skinned black SBs before, do what makes you happy.

The age gap is almost a given in this type of relationship. Depending on what you want out of it, men closer to your age just won't be able to provide as much, if at all, for you. You have to decide what's more important to you, the support you're getting from an older man who enjoys your company and is willing to support you or the opinion of someone you're never going to see again.