My parents are 65+ and are traveling in C TLV-IST-EZE;GRU-IST-TLV. They travel rarely (~once a year or two), so I'm looking for a *A program with good redemption, and especially allowing to combine two pax on one account.

(1) What is your home airport? TLV
(2) What types of fares do you usually buy ? cheap Y or C
(3) How many miles do you usually fly each year? 15k miles in C once (each), but mostly 3.5k miles every 1-2 years.
(4) Do you have any kind of status at present? What is it? No status.
(5) What is most important to you in a FFP? Long expiry time and reward availability. Ideally, be able to get a ticket from TLV to Europe of two after the one flight to EZE.
(6) Which routes do you fly most often -- TLV-BER or general leisure travel to Europe.
(7) Preferred Airlines -- No preference
(8) Do you travel for work or pleasure? All travel is for pleasure or to visit family