Not only for the 'retail' distribution policy, but the large number of sets being made. I don't recall any other issues being 'limited' to 10,000.
BTW, as far as OPs organ playing, don't expect a "B-3" sound. I don't know how to describe it, it's a bit unusual, but it works in context. It would be interesting to hear why that instrument was chosen for those sessions.
This same statement was included in the info for the recent Mulligan set.