cracked exhaust on 912ULS

Does anyone know the alloy of stainless steel used for the 912ULS exhaust system 973-387?  My welder wants to know before they attempt to weld my cracked exhaust.  

I have a new exhaust system on order (973-383) but it will not arrive from advancedpowerplant for another 6 weeks.   I would like to weld the cracked muffler to use until the replacement arrives.

As an aside, I am hoping that the newer 973-383 design will last longer.  This exhaust cracked at 900 hours.

Engine Serial Number: 6785083

Engine Type: ROTAX 912 ULS

Engine Version: 912 ULS2-01

Model Number: 309120110

Production Date: 08-Oct-2015

Thanks!

Scooby