I have a Utilus 10, diesel powered, about the same vintage. The safety valve was originally set for 225 bar, and currently set for about 300 bar. I have a new safety valve standing by. I’m happy with it.
I believe the 15 year thing applies because of the unknown number of cycles at unknown pressures, cyclic stress failures. The filter housings are not hydro tested. They don’t want you to sue them if and when the filter housing fails. I think I read of filter housings of this vintage failing somewhere.
I pucker up each time I fill. There was a video of a filter housing failing in use, may have been an Alkin. A new Bauer housing is expensive, about $1K or more. Might be able to cobble together a Chinese filter for much less.
If the U10 is functional, I’d go with it, a deal at $1250, and parts are readily available. Use the existing housing at your own risk!