EOD is 7 injections in 14 days (2 weeks). AT 500mg/week, that's 1000mg in those 2 weeks. So 1000mg/7 injections is 142mg/injection, or 1.42ml eod.
Easier would be to go 525mg per week, which is right at 1.5ml eod. 1.25 ml would only be 437.5mg per week.