There are focussing stages used in macro work to make fine adjustments to the camera position without having to move the tripod. While I wouldn't suggest using one of the commercially-available models under your 7x17, the basic concept, rotated 90°, could be employed to accomplish what you describe. Essentially, it would be just two interlocked wooden plates with a threaded rod to adjust relative position.
That said, getting Mr. Ritter to add front shift may not be all that expensive. I'd call him and get a quote.