I need a structural engineer to create chimney penetration drawings.

Looking for a structural engineer to design a wood-framed chimney enclosure projection through an existing roof assembly (1:1). We require detailed construction drawings. Please see attached representational sketches of the proposed chimney location and dimensions. Chimney penetration should include half-inch plywood to receive building wrap and CertainTeed cedar impressions double seven-inch straight edge perfection shingle system. Note that the proposed chimney enclosure will only contain a propane gas fireplace exhaust vent pipe.