Question for Artists: Adding to another artist’s work?

So I got a snake tattoo about two years ago on my ribs by a rather careless artist. He was older and I later found that he would use other artists’ works directly on his customers if they asked for it, rather than sketching his own interpretation. Anyway, I since moved about 1200 miles away. I want to get flowers/vines added around the snake, as it feels a bit plain on my ribs. Would an artist generally be willing to do that? Would it be rude to ask? I don’t want to go back to the original artist because of his poor work, but I’d love to get more around the piece. Thanks!