Assuming it's been maintained, 115K miles is not too many but it is not a Cat million mile engine. Many making less than 250 HP only make it to 400K miles. 10K miles/year is double what most MHs get so it's been well used. I would not let the miles be a deal breaker as long as the rest of the MH is in good shape. You want to make sure all systems work, especially the NoCold 1200 refrigerator. Do an advanced search (top L box above) on Norcold 1200 if it has this refrigerator.
Since you are new on here, you need to check the DOT date codes on the tires. Many on here replace their tires at 6-7 years partly because the 5K miles/year is actually hard on tires as they sit too much... not a problem with this one. Hopefully the tires are less than 4 years old as older than that I would replace the front two tires and most would replace all as you do not know how they were maintained or abused.
PS: It's hard to do an inframe overhaul on a engine that does not have sleeved cylinder liners and welcome to RV.net.