I bought the same steering wheel from another German seller for 175EURO and the airbag (used) from a US supplier for 300$...for the Airbag I had to wait for a month to find one (at a descent price)
If the auction closes below 300EURO, it's a good deal.

Most German sellers on EBAY don't use PayPal, to avoid commission, they prefer Bank transfers, this shouldn't scare you.
I don't see a reason NOT TO TRUST this guy, 169 positive feedback!!!

PS. Sold my old steering wheel (4spoke) with airbag, after replacement, for $320, so costs can get lower...