If you don't plan on doing any trailer sailing and just plan on having a trailer that will take her to the ramp once a year for her to be placed on a mooring or slip, I suggest that you buy a 23' tandem axle powerboat trailer that will take the weight of your boat fully found. My Long Mfg Trailer is Aluminum and can take 4600 Lbs. At any rate, you want a trailer that is built for a boat 1' longer than your boat. My boat is 21' 9" and my Long was built for a 23' boat.
It doesn't have to be a sailboat trailer. It can be a powerboat trailer. You'll need to raise the bunks high enough to accommodate the depth of the keel. So the extension brackets under the bunks need to be at least 24" high and preferably adjustable. The reason for the longer trailer is to be able to float the boat on or off the trailer with no need of tongue extension brackets for fear of swamping your towing vehicle.