Hi @FaceBiasBee678,
The Analyze > Multivariate platform has a Kendall's τ option that might be what you're looking for. I'm not familiar with ProUCL, so I might be answering completely incorrectly.

When you mention looking for something equivalent or close to equivalent, can you clarify what exactly you're looking for? For example, do you need a non-parametric test for correlation between variables (Kendall's τ might be what you're looking for), or are you just looking to see if there's correlation between 2 variables (Fit Y by X > Fit Line might better suit your needs)?