** Shares of British financial services provider Alpha Group ALPH.L jump 25% to a record high of 4,155 pence
** Stock top gainer on FTSE midcap index .FTMC
** U.S. payments firm Corpay CPAY.N to acquire ALPH in $2.2 billion (1.6 billion pounds) cash deal
** Including session's gains, ALPH shares up 77.63% YTD
($1 = 0.7387 pounds)
(Reporting by Unnamalai L in Bengaluru)
((Unnamalai.L@thomsonreuters.com;))