The off-gassing will take quite some time. I would not use spray paint of any kind.
Look into the pour-on epoxy bar-top coating. It cures quickly. Once cured, zero odor and perfectly safe.
Another idea is to ditch the wood idea and get yourself some closed cell PVC. One brand is "Sintra". You can find it at sign shops and from online plastics suppliers. You can cut it with a saw or score it with a utility knife and straight-edge, then carefully break it along the cut. Completely safe and waterproof, and it can be heated with an undertank heater if need be.
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Antaresia maculosa
Antaresia childreni
"Pythons the size of kingsnakes and with slower metabolisms"
Mark G