The 'right' anchor function places the anchor of the link in the middle of the right side of the view bbox. It accepts three arguments, which can be passed within the anchor.args property:

rotate boolean Should the anchor bbox rotate with the end view? Default is false, meaning that the unrotated bbox is used.
dx number Offset the anchor by dx. Default is 0.
string Percentage strings (e.g. '40%') are also accepted.
dy number Offset the anchor by dy. Default is 0.
string Percentage strings (e.g. '40%') are also accepted.

Example:

link.source(model, {
    anchor: {
        name: 'right',
        args: {
            rotate: true,
            dx: 10,
            dy: '40%'
        }
    }
});