you can buy 500 tickets from the shop, so i think it's okay to do a little excursion to the land of manyus
4300 tickets for all rewards. subtract the 500 from shop = 3800 tickets. divide with 14 (days), so you need to get around 270 tickets a day.
if you run the 80 stam stage 7 times a day you already have enough. and don't forget, that the stages in phase 2 will be more efficient, so there should not be a problem getting 4300 tickets in total.