They may be the Bargman 68 series lights. If they are, the number 68 is molded right into the front of the lens, easy to read.
The outer lens and the body of the 68 fixture are one piece, glued together in some way, so you can buy just the outer lens. You have to purchase the entire fixture including the socket, bulb, and pigtails.
I needed to replace them on my '99 and found a great deal on ten of them on Ebay. When I replaced the lights, I didn't replace the socket and pigtails unless there was corrosion or other damage to the socket. Otherwise, I just cleaned them and reused them.
On my '99, the high five DOT lights and the high two on the front had a bead of caulk across the top of the fixture. Came that way from Sunline. I opted to caulk the top and sides of all the fixtures, but left the bottom uncaulked to allow water to drain if it gets behind the fixture.
I also upgraded the entire trailer to the 194 LED's when did this job.
While mine came from a great deal on Ebay, there are other online sources including Amazon's search engine.
One final note: These fixtures are NOT RV specific fixtures and they are NOT Sunline specific fixtures. If you have a local auto parts store that carries Bargman products, they can likely get you these lights at a good price, too.
'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
1999 to 2011: '99 Sunline T-2453
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