I'd seen the reference to SECO in the listing of a Stuart tank in Florida on eBay several months ago also
SECO imported many AFVs, including Sexton SPGs, M5A1 Stuart tanks, M75 APCs, High Speed Tractors, etc., etc., all slated for conversion for the logging/mining industry. Not sure all their conversions were a success. Perry Kitson, one of our forum members bought a Sexton from them, which he is currently restoring.