Colt will research the background of your pistol and give you a written report. For the 1902 Sporting, they would charge $100 for researching their archives: http://www.coltsmfg.com/CustomerServ...eServices.aspx
Flayderman's Guide list the value of your early Sporting at $500 in Very Good condition. Without additional photos, it is hard to say for sure if yours would be considered Very Good. Serial numbers started at 3500, so yours with no. 5290 was early. Production ran from 1903-1908, so yours would be from the earlier part of that range.