My horses is a 16HH Paint/TB and I would classify him as "medium wide," likely leaning more towards wide than medium.
I used to ride in a 14" seat but have definitely gained weight since then. I'm either a 15" or 16" now (5'6", 170 lbs).
Option 1: Used Circle Y. It is obviously the most expensive option, and is definitely a used saddle. Seller thinks it needs to be refleeced, but due to the location of the missing fleece, I don't think it actually needs to be done. 15" seat, 6.5" gullet. I'm concerned it might be a bit narrow. No return option.
Option 2: No name off Ebay. Actually looks like a decent enough saddle, price is very low, shipping is a bit high but the price is low enough so it doesn't really matter. Seat is 16", gullet is very wide (8+ inches). I'm concerned it might be TOO wide. No return option.
Option 3: No name off Ebay. Looks like the "cheapest" saddle, but still not as bad as some of the knockoffs I see listed all the time. Black color looks to be rubbing off, though. 15" seat, no info as to gullet/bars (I've asked the seller and am awaiting a response). Same price as the last no name, much lower shipping. 14 day return policy, not including shipping.
Option 4: Jeffers Equine saddle. Is technically a "no name," but looks to be well made. I actually had a very similar looking saddle from Country Supply many years back and it was one of my favorite saddles ever. Price is nice, shipping is free. Full QH bars, 16" seat. 30 day return policy, I'd have to pay for shipping the saddle back. It's on backorder for a month, though, so that's a bummer.