Jul. 21 -- Tin's supply-demand deficit is set to narrow, possibly even moving into surplus in 2011, Sucden Financial says. This will add to the currently increasing stock levels, although the potential surplus will remain vulnerable to any unexpected supply disruptions, the broker notes. The rise in stocks is a factor of destocking, the broker adds, initially as high prices earlier in the year attracted metal into warehouses, followed by consumer destocking after the events in Japan. Tin is expected to average around current levels in Q3, with an upper average level of $29,000/ton in the event of unexpected supply disruptions, Sucden says. Support should be found at around $24,500/ton, it adds. LME tin trades at $27,890/ton, unchanged from Tuesday's close.