No budget for what are clearly essential calculations ....... Class 1 nuclear ........ Does that make sense ? What kind of project is this ?

Don't rely on the opinion of contributors to this forum to provide non-code SIF's, that data will not stand up in a fatal accident enquiry.

Get onto PRG (FE-Pipe)or other FE code supplier, otherwise this might be a project you will be scrubbing from your CV, one day in the future.