I've always thought horns like this would be handy to have. For one thing, it would be fun to play a front-facing horn sometimes. But if you are taking a trip, this would pack better and you would not risk your good horn just to have something to practice. There is a choice of a cheaper, rough model and a fairly nice looking King with a brushed finish for more money (but it has a make offer button):
King 1124 Marching Baritone ($750):
https://www.ebay.com/itm/334763105960
This one sold (undisclosed price)
DEG Dynasty Marching Baritone (bid $175, buy now $425):
https://www.ebay.com/itm/285159377481
This one sold for $204.48