They should deduct VAT from everything but the shipping charge (that's a service delivered to them, so not deductible as goods for export outside the EU. They refer to VAT deductions on their pricing so I can't see why they wouldn't. VAT in Hungary is 27 % so:
(420 + 30 + 20) / 1.27 + 35 = 405 Euros = $541
That said, I've heard horrible things about duty and brokerage fees from couriers in North America, and I don't know what your transaction costs will be. As I understand it, Vass don't like to use the local postal service to send via EMS, because they've had problems with them. The downside (and I've found this where I live too), is that the EMS parcel delivery (used by most postal services) tends to bypass the whole customs thing pretty easily, even though it's slower. But Fedex DHL etc always end up paying the duty and claiming it back from you. Where I am, there are no fees for that, and duty is only 5% anyway. But still, it's an annoyance.
I suspect that if you're receiving via Fedex in North America, and taking into account exchange and bank transfer fees, it might end up costing you that $100 difference: the proxies who can post to you via EMS probably save you everything they make. I'd probably go direct, but if I were in America I might well use a proxy.