Good bitrate to encode a 720P 59.94 fps VHS transfer for Blu-Ray?

Captured some VHS video, deinterlaced to 59.94, cleaned it with NeatVideo, upscaled it to a 1280x720 picture (960x720 in a 1280x720 pillarboxed frame) to transfer to Blu-Ray.

DVD Architect Studio default is 18MBPS, what bitrate would you consider overkill for this kind of project?

Thanks.