Adler Barbour power plate

I have the pictured refrigeration evaporator plate and lines that came with my vessel. I think it is R-12, because of its age, but cant say for sure, it is fully charged. I contacted Adler Barbour in Pompano Beach FL via e-mail with the serial # 22636 asking about type of charge and they were no help.
So I offer these up for sale knowing they may contain obsolete freon, and thus not knowing what they are worth.
If someone knows whether or not i can convert the plate to 134A (yes i will recover the R-12)I would appreciate it as i may just keep it and purchase a compressor/condenser unit.
I only need to cool about a 2 sq/ft box, so this unit may be overkill.