I don't know of any other 12v solenoids repro'd other than 5th avenues. Will confess to never measuring an R11 solenoid which is what I assume is in the car. Maybe someone on the forum knows if the V8 OD solenoid will fit.
One possibility with the original is a voltage reducer/regulator to supply the OD system. If they left the OD solenoid alone, I'm wondering how the rest of the conversion was handled -- resistors or ??. Several things besides the solenoid are high current draw -- blower(s), radio, etc. How each was done might be a good question to ask.
Here is a unit that has been linked and mentioned more than once on the forum as a possibility to supply various items. Sounds like a good approach over resistors. He specifically mentions OD as one of the uses but I do concur with his recommendation for the 20amp version. Usually there are a few on ebay. Today I only see his 15amp.
Voltage RegulatorThis Post was from: https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=112189