> How can I market this?

I think you slightly late, at least for Laserdiscs - they are gone to history, now all new video already digital from beginning.

Few years ago in 3rd world, was popular to make business for digitally archiving old analog home archives. Scheme was simple - just rent cup of square meters in some crowded place and gather clients.

If it could fit other cases, business schemes could be very different, depend on case.