I just purchased this bundle from G2A. Gift card keys came straight away.
The link in the deal goes to the page for a ₺100 gift card.
If you scroll down the page, there is a box showing an exclusive deal of ₺100 + ₺75 gift cards for $22.78.
I was able to successfully add this to my Turkish Netflix account. The gift cards came individually.
My bank card I used for Netflix has now expired and I'm unable to add a new one as I have to verify my Turkish mobile number. Looks like it'll be gift card for me from here.
Here's a how to on activating a Netflix account via VPN without a flight to Turkey
Note: these can not be used on any other account apart from Turkish Netflix accounts.
Edit: As pointed out by @snuke, this is not the cheapest way to get Turkish Netflix. Cheapest way is through a foreign friendly credit/bank card. If you do need to update your details, you'll be able to do it as pointed out by @doweyy
Just an FYI OP, you can bypass the mobile number requirement to update payment method within Netflix by live chatting and asking for the secure payment method update form to change your payment method. I had the same issue and bypassed it using this.
Nice timing. My turkish netflix just ran out of credit on the gc.