Here is a MINT condition YSL-448G from Yamaha.

Large-bore (.547), F-attachment, 8.5" one-piece gold brass bell, string linkage, and yellow brass outer slide. This horn was used very briefly by a young player who decided to move to another instrument. His loss; your gain. Perfect condition - I can't find a single sign of usage on the horn. Case and all accessories included EXCEPT the mouthpiece. He lost it.. Slacker! I can include your choice of Yamaha 48, Bach 6.5AL, Bach 6.5A, or something similar. I have boxes of mouthpieces...

https://photos.app.goo.gl/2nBf6gDDaswrA9uE8

These sell new for $2000 at WWBW. This one is $1250 with free shipping.