After WWII Gecado became Dianawerk. My Catalogue list the Diana Model 35 as being made from 1953 to 1987 under several different Variation's. Without more detailed information it is hard to identify the exact year for you. But considering that you asked for it by it's original name I assume it would be one of the earlier variations.
20 pound
To determine the value of "Gecado mod 11 kal," we first need to clarify what "Gecado" and "kal" refer to, as they could represent numerical values or variables. Assuming "Gecado" is a numerical value, you would take that value and divide it by 11, then find the remainder. Without specific numerical information, I can't provide a direct answer. Please provide the numerical value for "Gecado" to proceed.
1959
Please check the link for the Manufacture Date codes details on the Remington Society of America.
No way to answer without the serial number.
1977
1967-1988
@1970
@ late 1975 or early 1976.
1908
No way to answer withou knowing who made it.
1969