Hello and welcome. Since you’re looking for Savio, have you tried their website? Websites are good about including links to retailers (either online retailers, or brick & mortar).
As far as whether to go with a kit vs buying individually, there are members here who have done both, so maybe some of them will chime in with their experiences. I bought all of my components separately, because at the time, I wanted that choice rather than having to “settle” for what came in the kit, but that choice will come down to convenience vs practicality vs economics vs any number of other factors.
The most important purchase you will make is the liner — don’t economize on your liner. Pumps and filters can be replaced fairly easily, but if you get a cheap liner…..you have to quite literally restart from the ground up!