Ikomat and Ikonta are the same camera, Ikomat being the earlier name. Neither the Novar lens nor the Derval shutter have serial numbers which makes dating the camera harder. There should be a serial number consisting of a letter and four (five?) digits - the letter gives the year of manufacture. I don't have a list for year letters but you might find them on the Interweb. It is definitely between 1931 and 1938 (the years they made the Ikomat/Ikontas.