Ask HN: Kickstarter asks me to pay more through email, what to do?

I backed a kickstarter campaign in the hopes of getting an awesome product, something that I passed on the first time for being a first version but that now I feel confident they have made much better. So I backed it choosing the reward I wanted and paid it.

However, after completing the campaign someone[1] sent me an email asking me for more money to complete the payment and shipment[2]. Since the email looks legit, I hovered on the link only to realize to my dismay that it's in http (not https). Nonetheless, I followed it t an official pebble website only to realize that, after few pages trying to make me buy some more products, they just offered a form that looks like another famous company form[3] asking me to write my credit card info. I didn't check into the source code to see if it's the official one, nor I think I should be required.

So these are strong indications of scam for me:

1. Ask me to complete a payment through email.

2. An insecure and easy to mitm link to complete the payment.

3. Only allowing to write my credit card details, while the official shop[4] accepts paypal and others.

Is the company as sloppy as it seems or am I being scammed? If relevant, the company is Pebble from which I would expect a high quality checkout process.

What can I do? I don't mind paying 10-20$ extra so I could just cancel the order, get a refund and then go to their website and buy it using the official way with paypal. I do care a lot about not giving my credit card details, specially given the 3 points above. And I also care about the timeframe, because as a backer I would receive it much earlier.

[1] probably the campaign organizers

[2] The campaign said I could have to pay more

[3] http://stripe.com/

[4] http://pebble.com/