For a new trailer.....
Since you are in Florida, you could contact Performance Trailers in Clearwater. They make the trailers for the Precision 18, which is a similar size and configuration (shoal keel/centerboard) to the O'days.If looking at used trailers, you'll want one with a gross capacity of 2000lbs or more. A trailer with that capacity will likely have a single axle equipped with 13 inch wheels. For easy launching it should have a dropped axle (spindles above the axle beam) and the cross members should be formed in a shallow V, not straight, so the boat can sit as low as possible. Since there are more used trailers around for powerboats than for sailboats, some adaptation may be required - You will need a center bunk to support the weight of the keel and the side bunks may need to be extended up to reach the hull.But first we should figure out which model O'day you have. Production of the 192 had not yet started in 1982. So, you either have a newer boat that is a 192, or a 1982 O'day 19, the model just previous. If you can post the Hull Identification Number that is molded into the transom, the date of manufacture can be determined from that. Either way, you have a good boat that should provide you with a lot of fun.