Probably, but they will add the VAT to get a comparable price to pricematch against.
7dayshop is based in Gurnsey, so outside the remit of UK VAT, you are personally liable to VAT on the import, but the Royal Mail as collecting agent are not very good at their job, so you usually don't pay the VAT.
Thus if 7 day shop were advertising a product for £200, then the price match value would be £235. Jessops have a central call centre that these price match approvals are done with, so I am sure they would be wise to the pricing of 7dayshop.
I personally don't place much on the Jessops price match. They would price match the Canon A80 for me, but not throw in the 128Mb card that Argos were giving away

, so I bought it from Argos