Our 80s Cabanon tents don’t have it. But my mechanic got something for my car from an agricultural engineer, who made something bespoke (a metal rod with 2 right angles, a male end & a female end). Farmers need odd shapes to keep equipment going.
Someone might come on here with a website for tent parts too - might help to know what tent you’ve got.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.