2 return-tickets for City Airport Train (CAT): Vienna.

Return tickets = one trip from Vienna airport to city and back
OR one trip from city to Vienna airport (like Arlanda-express in Stockholm).
Full information: https://www.cityairporttrain.com/en/home

Unlimited validity for both tickets.

Price for 2 return-tickets (total: 4 trips) = 400 SEK.

I can send the tickets to you via Post or you can pick-up in Stockholm.