Spacing canti bosses

[ApolloCVermouth]

I hope that this isn't a dumb question. Does anyone make canti posts that can be brazed to the sides of a fork? The reason I ask is that I've found on my last bike that canti bosses brazed onto an old sport/ touring fork are just too close together to allow for proper tension on a v-brake. I imagine the same would be true for a canti brake but I don't know.
Thanks