As you probably know Sun Valley Inc. the manufacturer of your trailer is out of business, so you cannot get one from them. One thing I would do is Search eBay. I have seen RV owner's manuals pop up there all of the time.
I am opening up this question to our visitors. Hopefully one of them can provide you with some information on where you might get this owners manual.
If you have an answer to this question please click on the "Click Here To Post Comments" link located near the bottom of this page.
Everything-About-RVing.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com.