Just looking at the back cover of the latest NG&SL Gazette. That space is usually taken up by a semi-local supplier, PBL. They specialize in Sn3, and have beautiful, fully painted brass models shown, but only in Sn3. They have been in business since 1979.
This month, they announced the possible production of a series of Shay locomotives in O and On30! The accompanying pictures are of their latest S-scale models, but they are asking potential customers to contact them if interested in O-scale models. They indicate that they will produce these if there is enough interest.
Anyone interested in these superb models should contact PBL. Their website is: https://www.p-b-l.com/