Are you wanting something cheap and cheerful that will fit but may not be an exact colour/brand match or are you looking for an Outwell extension of same colour?
OK your tent is 300cm wide and 195cm high at front pole which is set 140cm from bottom of the sloping door.
The Outwell Monterey 4 extension is a close fit at 320cm wide x 220 high x 280 deep allowing 140cm of covered floor space (remember that sloping door).
If cost is more important you can buy the Gelert small end porch which is available in green or grey, being enclosed and nearly half the price. It's 300cm wide and 205cm tall so should be a very good fit, it's also 335cm deep allowing a little more floor space.
Don't forget to leave a review of all tents you've used, for a chance to win fantastic prizes
Or if you can get one the earlier Vango Icarus 500 front Canopy or Extension will fit. There is a pic of one on an oregon in the tent review section under Outwell Oregon
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