You could try a local caravan stockist, we bought ours second hand when we bought a new caravan and the man there said that they always have odd poles, etc. Might be worth asking locally (they were the Caravan Company in Leicester).
We have a Eurovent Sancerre awning but we have fibre poles. I'm not actually sure what you mean by pole brackets. If you can't get what you want locally Renishaw seem to have a good selection of on-line spares (see here). If you mean the pads that the roof poles fit onto the side of the van (like the Quick lock pads) then I know Jacksons of Arley have some in.
I'm replacing the Eurovent pads with Dorema quick lock pads. I know the secondary beading is smaller than the Dorema so I intend to pack the quic-locks with some very thin plastic. Hope it will do the job - not keen on the Eurovent pads.
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