Last time I wandered in, I came out with 2 lovely 7metre poles for £6.99 a shot.
Excellent value 
@YO8SEP : speaking about fishpole supports you should consider this, it really rocks!
FISHPOLE SUPPORT - 12 euro
I bought one of this type last summer in Italy and now I cannot go on SOTA without it, hihi!
Hi, although I don’t have one, I hear from some of the US activators that the magnetic loop is probably the easiest and quickest to setup and get on the air. Performance is not going to be quite as good as a full sized wire antenna, but I understand that it is within an “S” point or two on 40m and not much different on the higher bands. Certainly an option for you to consider (and one that I am looking at for some possible travel next year - the walkham magnetic loop certainly seems to be a good product that gets good mentions).
Over the last 18 months I have been using an OCF dipole cut for 40m supported by a 9m squidpole which gives me all bands 40m to 10m with the assistance of a tuner to help on the bands it is not resonant. Performance has been quite good with a lot of DX worked as well as significant numbers of local VK contacts. My squidpole is usually lashed to a tree, a stump or anything else I can find to support it on a summit.
Matt
VK1MA
Hi Andrew, inside diameter is 48 mm, and the spike stores inside for packing, as you can see on the picture on the Decathlon site
73
Luc - ON7DQ