Do not know where to get a used one, but there are RV surplus houses that have new ones a lot cheaper then new from a dealer.
This issues may be freight but if you ever end up in the Elkhart IN area there are several of them.
These guys I hear are top flight. We have had several members make a run there. I will make one myself I hope this year.
Bontragers Surplus Inc.
These guys I'm sure have one as I have been there New and Reconditioned RV Parts & Accessories - RV Surplus
You would have to call with your door frame size. They sell them with door,frame and all. I do not know if they ship.
There are used RV parts places out there. Used RV Parts - Colaw RV Used Parts and Accessories
Again shipping may be an issue.
There are also many part places that sell on Ebay. Gosh there was a post here about a month ago on an Ebay place a member posted. They had cargo doors and etc a lot. I can't find that post right now, if I do I'll post. But an E bay search for RV door or Travel Trailer Door may turn up a lot of options.
If you want to see how the door and frame goes in, see here.
You may need to buy the entire frame and all. If you are lucky enough to have the exact same model/brand then maybe you take the door off the new frame and put on your existing hinge set. Or change the entire frame and all if it is not exactly the same.
How exactly did you loose it?
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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