If your Trillium
still has the awning
rail securely attached, either a rope-and-pole awning or a bag awning will work. The difference is that the rope-and-pole style is not self-storing- you have to remove it and store it inside the trailer or tug when you break camp. A bag awning stores in its own bag that hangs from the awning rail in transit. It's still a good idea to remove and store it indoors between trips because water can work its way inside the bag.
Vintage Trailer Awning
Classic Bag Awning | ShadeMaker Products Corp.
Another option is a free-standing canopy. Our Scamp
did not come with an awning rail or a newer-style case awning, so we just use a 10x10 FirstUp canopy we already owned. It's somewhat heavier than the attached types and takes up space inside the trailer when traveling, but it has several advantages that make it work for us. It's much cheaper (about $100-125 for a decent quality one; make sure to get a straight-leg style). It can be set up away from the trailer to take advantage of shade or views. It's sturdier in the wind and doesn't shake the trailer when the wind does blow. It can be set up next to the trailer, but the legs may have to be raised a few inches for the door to clear. You can also buy side panels, either screened or solid.
Here's our FirstUp taking advantage of a shady corner of our site at Lost Dutchman State Park recently, while the trailer had to remain on the paved parking pad in the sun.