I read that the effects of receiving the full post exposure rabies vaccine could last as long as 10 years. Is that true?

Don't plan on it. Most consider it reliable for protection for 2 years after completion. They recommend that those in high risk jobs known exposures be tested for level of protective antibodies at that point. If declining, they recommend a booster. Some just get a booster at two years.
Get titer checked. It may be true, but if you have continued exposure, then you should have the antibody titer checked. Discretion is the better part of valor!