Personally i would say put it off for a while and save a few more quid and get slightly different items.
1) 10w/40 Motul oil is fairly cheap on Ebay anyway, £23
2) K&N air filter off Ebay, about £32, but the only one you'll ever need to buy for the life of the bike
3) K&N oil filter, the one with the nut on the end, you'll thank me for it later! £10
So actually only £12 more in total, but you'll save money in the future anyway because of the K&N air filter