Dear Janos,  I'm not entirely sure of your description of the
positioning of the combs in this box, but I'm assuming it's the typical
Symphonion arrangement where the pressure bar crosses the entire disc
and each of the two combs is at either end of the pressure bar, thus
basically crossing the full diameter of the disc.

If this is the case, the tuning scale is published in Graham Webb's
book "The Disc Musical Box Handbook."  If you do not have access to
this I can send you the appropriate page.

I'm not sure of your experience in tuning musical box combs but one has
to be very careful to NOT use a tuning device that restricts you to an
un-stretched equal temperament.  Also, with the tuning given you should
be aware that you may have to transpose it to a different key for that
particular box although the intervals will be the same.

Hope this helps.

Jim Heyworth,
Sechelt, B.C., Canada