There seems to be a difference between the available Store Credit of yours with the site currency you had picked previously. Would you like to:
Gift card adds 100 SAR to your AppStore account. You may use it only on Saudi Arabia accounts.
No expiration date.
Itunes & Apple Store GIFT CARD USD $34.99
Itunes & Apple Store GIFT CARD USD $43
Itunes & Apple Store GIFT CARD USD $200
Itunes & Apple Store GIFT CARD USD $2.89
Itunes & Apple Store GIFT CARD USD $28.75
Itunes & Apple Store GIFT CARD USD $13.08
Itunes & Apple Store GIFT CARD USD $5.99
Itunes & Apple Store GIFT CARD USD $37.95