Coker will need them to replace the boiler. We recently got a bid to replace the firebox and boiler (no smokebox or any appliances) with a brand new one for an engine about or a little smaller than a K28. The tab was over $400,000 FOB Portland, OR. We would have to add all applliances, mount the boiler, build a smokebox, etc. It's not cheap.
With the new boiler regs, and the structural specs of boilers built before 1914-1920s, replacing the boiler may be the most economical way to avoid lowering working pressure. That's going to hit a lot of small operators hard.