Hi JDuvall,
Welcome!
They sell new door units; you must buy the entire door frame and door. The size they go by is the rough wood opening, not the physical door size. They are costly, $500 to $700, with freight.
Lippert is one brand that makes to order. Here is their main website
https://store.lci1.com/right-hinge-r...-sq-entry-door
You need to call them and get a quote. Do not order something that is that custom from their web store, as you may not know which features to order. They are helpful and ask for customer service for entry doors. I bought a new cargo door to replace one in a Sunline I was helping repair; they did a great job on it and less cost than I thought.
EBay also has some, there are many leftovers, still new, a good deal, and less cost, but they may or may not have your size. The other issue, your rough opening is for a square top door; many of the RVs now have curved top doors.
Pelland also sells square entry doors.
https://www.pellandent.com/RV-Entry-Door-Replacement, and they are out west closer to you. They buy from the manufacturers and then resell them. They might, by luck, have something in stock. I have bought from them also, and they are good to work with. But again, the cost is high.
Many of our members have rebuilt the older camper doors, mainly from rotting out. If you have all the old parts, rebuilding the door may be a lower-cost option. If you want to go this route, we have some posts with door rebuild pics we can hunt for.
Hope this helps
John
PS. Since you are restoring your Sunline, consider creating a post on it. It is really helpful for others to come behind you. And you can ask any question about it. Plus we like seeing all Sunlines.
We have some folks doing a 70's series rebuild now. Yours would be a great addition.
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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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