Give a call to the st@bkea in your area, they will let you know if they have horses that can accommodate the weight.
The average horse can carry between 30 and 25 percent of its body weight on its back. Many riding horses are only 900 pounds, bigger quarter horses are around 1200 pounds, stock horses bred for working cattle and some plowing are up to 1600 pounds. Many riding st@bles have either full blood or half blood draft horses that pull hay rides, they are also saddle broke and are used for people that need to ride double or super tall people, and heavy people.
My sisters 6’6” and around 400 pounds (very busty). She rides a half draft Belgian and Morgan that weighs in at 2600 pounds. The horse does packing on trails of 509 to 600 pounds and doesn’t sore or tier (tents don’t bounce or lean when packed properly). She was so impressed with the mare she bought her as her personal riding horse. My brothers 415 pounds and 7’8” and rides a Clydesdale named Big Jake. The horse is too big to drive because of his height, just over 19 hands and weighs in at 3400 pounds. The horse usually carries two special needs full sized adults but my brother rides him twice a week year round (indoor arena) when he rides the Belgian cross his feet are about 6” off the ground, if he tried a regular riding horse he would just have to stand next to it and swing his leg over its back, no jumping up.
The average stable has a 200 pound limit, however the one with draft3rs or draft crosses can accommodate 300 to 350 pound riders. As I said call and ask ahead of time. Many places appreciate reservations so they can have the horses up that are needed. My mother in law was a sweet petite thing, all 94 pounds of the 5’1” woman, short legs so th y usually had her on large ponied like hslflingerd or similar. She even rode a bigger dhrtlwnd as het feet eerie about a foot off the ground. The shrland was 700 pounds not fat.