Is there a way to calculate what the odds will be of pulling copies of R Riko on a non Rice/Riko banner?

I have 1LB Biko SSR randomly and am strongly considering throwing 30k or even 60k carats at said banner to try to MLB it, and if I do that I’ll be hoping to pick up at least a few copies of R Riko in the process. Not sure if there’s a way now to know what the odds will be once she’s added to the broader pool.