dont search for your car specific, just general brand. most places have alts for all cars. idk how much install would run cause i do all my own stuff, my dad own a body shop so i have learned over the years.
my uncle is very mechanically inclined....but im not sure if hes had any alt work....hes got a toyota supra...twin turbo and hes dont every upgrade from the intercooler to exhaust to headers to tuning the fuel management shit, ill give him a calll...im thinkin install wud run atleast 200 bucks
get under your car and see if you can get to it first ... if it is easy to get to try to do it yourself and save some money that you can use toward your 2nd batt