There's no "official conversion". Either you read the Satanic Bible and say "OK, this philosophy sounds like a reflection of me", or you don't. If you find that it matches your convictions, to the point that you can honestly identify yourself as a "Satanist", then you are one.
Note that the term "LaVeyan Satanist" is a redundancy. They don't use it. They were the first group in history that took up the name "Satanist" for themselves and made an actual, real-life applicable religion called "Satanism", so as far as I'm concerned, they have the title. There's already a different term for people who believe in Satan as an actual deity and worship it: they're called devil worshipers.
And it's 11 rules of the earth, not 7.
>>So I can't officially convert? what can i do then?
If you want to make your "conversion" feel "official", I suppose you could do a ceremony of sorts. "The Satanic Rituals" includes a sample baptism for adults. You could make something out of that.
>>Last time i heard you have to pay 200 $ fee to
>>join church of satan.
You don't have to join the CoS to be a Satanist. They even say this right on the website. But yes, that's what they charge for a lifetime membership. Considering that organizations like the NRA charge $1000 for a lifetime membership, I'd say it's ridiculously cheap. By the way, when you write prices, the dollar sign comes before the number.
I laugh a the people who are stupid enough to believe that the CoS is some money-making scheme. If they wanted to be a money-making scheme, 1) they'd try selling something that had more status quo appeal, and 2) they wouldn't be charging one-time fees.