Do they really have that many sellable players?
Quite a few are getting on a bit, others are nearing end of contracts, some are just mediocre and won't attract high fees. Arteta would struggle to find a good team willing to pay his wage when there are cheaper alternatives on the continent. That leaves Jagielka, Coleman, Fellaini and Rodwell.
Coleman represents a bit of a risk in that he may not improve much, Jagielka will only command a good fee if the right PL club goes for him, but I can't see a vacancy going at the moment. That leaves Rodwell and Feillaini, and Everton are ove the barrell - look at how easily they lost Pienaar.