Golden Virginia - definitely £8.80 (pounds sterling) for box of 5 x 50g
Old Holborn is £9.00 (pounds sterling) for box of 5 x 50g
Amber Leaf is the cheapest - around £6.20 for box of 5 x 50g
I'm not sure what Samson is but I think it is more than Amber Leaf but cheaper than Golden Virginia
When landing in Gib you still have to go through Customs in Spain so are only allowed the one box per person. It's the same flying back from Gib to UK.
p.s. It's better to "post reply" on the earlier/original thread than to start a new one each time you post ......