** Shares of Straker STG.AX rise as much as 24.4% to A$0.535, their highest level since May 23

** The language and subscription services provider heading for third straight day of gains

** Co wins European Union contract for providing translation and post-editing services, specifically for English text into French

** Says deal has an estimated contract value of 0.525 million euros ($612,255)

** Stock last up 9.3%, cutting YTD losses to ~17%

($1 = 0.8575 euros)

(Reporting by John Biju in Bengaluru)

((John.Biju@thomsonreuters.com;))