trying to find IF/where the wireless doorlock entry module is on my new 1998 4runner SR5.

car did not come with a keyfob, called the dealership and asked if my VIN had it installed they said they wouldnt know as it was a dealer installed option.

where exactly should i search (under the steering wheel collumn im guessing) to find the FCC part number that tells me which remote to buy if it has it installed.

im interested in adding it if my car doesnt already have it, would it be as simple as buying the controller like this one and a compatible remote ?
TOYOTA OEM RS3000 SECURITY SYSTEM ELECTRONIC CONTROL UNIT RS 3000 ECU | eBay

maybe its easier to buy an aftermarket system like a viper or something? (def dont want any oversensitive loud alarm though!)

thanks for the help with this new purchase