What model do you have? Some newer residential systems aren't crazy expensive (and totally worth it). If you can get the leak fixed, and for sure new filters - you can always test the water with a tds and a Toc meter similar to this one
https://www.amazon.com/dp/B08HNJLMP4?ref=ppx_pop_mob_ap_share
That way you can check for any bad stuff in the water. I had one system sit for about 18 months once. Changed filters and gaskets and was working and filtering like new.
You can get a TOC meter like this on Amazon. https://www.amazon.com/Analyzer-Bacteria-Pesticide-Detection-Drinking/dp/B08HNJLMP4/ref=mp_s_a_1_4?dchild=1&keywords=toc+meter&qid=1626618244&sr=8-4