go to Inland RV. You will find them on this web. I recently had to replace the entire door lock on my 1986 31' Sovereign. The original lock is no longer produced. A used "original" was around $500.00. The replacement had to be reto-fitted. I am guessing that is the case with your earlier model trailer. The replacement cost was $154 including shipping. A local locksmith had it installed within an hour. It looks and works great, but did require a back-plate of stainless steel in order to mask the previous holes, inside and out. Good luck.
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