It could be an aerial mapping lens, but there isn't much call for those to be f/4.5 since they're generally shooting stuff under Sunny-16 conditions.
As to the price, it could be part of a money-laundering operation. Crappy old lens (unusual or obfuscated enough that it's hard to argue its real market value) goes one way, big sack of cash goes the other and the eBay transaction legitimises
The lens, well, it smells like a 400/6.3 Telemar-17. There are several on offer on eBay at much lower prices. See the 1963 GOI catalog, which can be downloaded from: http://www.lallement.com/pictures/files.htm If you look in the catalog, you'll find two other 400/6.3s. I'm pretty sure it isn't an Arktik-A or an Ob-87. None of these lenses has anything like the claimed coverage.
It is as typographic error. Bear in mind that in the anglo-american world dot and comma have an opposite meaning concerning figures than in other ports of the world.
I once erroneously typed in a bid on a US-site german-wise and also got something of that kind. But was warned by the system....