After replacing my second original Seiko strap, i contacted with the dealer in Spain to get another one. Price is aprox. 35€, but the main issue is that it might take up to 3 months for delivery. Found this one, and purchased two. The quality seems to be very good, and i like (as mentioned earlier) that the strap is 20mm in width (original gets narrower to 18mm). It comes with two pairs of spring bars, which fit perfectly, but i think the original is much better. Maybe if Zuludiver made the hole for them in the strap a litle bit bigger (just a little bit), it would be perfect.
Now waiting to see if it last as much as the original.