If I had known, I'd have written...
There are photos of 130mm launcher and OT-62 from 1973 war in Concord's "Tank battles of the mid-East wars". I think it's safe and better than nothing, to assume +/- 5 years - though of course you might not agree. Considering, that the launcher was designed by 1956, and OT-62 in 1963, I guess, that they were bought even before 1967, but I have no proof. Maybe even before 1956, in case of 130mm launcher, since Egypt started to buy tanks from Czechoslovakia in 1953.
Regards
Michal