There are many aluminum extrusions or brake shapes that would work. Find a real building supply store and you should be able to find clear anodized aluminum angles in 8 foot lengths (often used for door and window installation). Fry Reglet makes all kinds of aluminum shapes that might work and could be purchased from a local building yard or window/siding installation company. An RV supply store might be very limited in terms of what is actually available out there.
Cameron & the Labradors, Kai & Samm
North Vancouver, BC
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