There has been no confirmation that china has R-27RE. Do show me a link to some reliable source for confirmation, i'm really interested to see it. Even if we assume that china has them in great numbers, it is still nothing close to a silver bullet. It's semi active for gods sake. You need to keep lighting up the targeted aircraft with your radar the whole time of the flight. That pretty much means very steady flight. Which in turn means the incoming amraams, however shorter range they might have (and current advertised max range is 75 km for newest version) could go without the midcourse trajectory update and still make a rather precise killing in the end. Yes, if you're suicidal you could probably kill an enemy fighter with a R27RE, but its very unlikely you'd survive it, too. Not to mention it's still probable amraam is more precise.
If my information is correct, no russian sold Su27SK can carry R77s, as stated, but some last 40 or so chinese built J-11 have been modified during production to carry R77s. Furthermore, a possibility of a comprehensive update of all the SKs and J-11s is being evaluated, with $5 million per plane, giving it newer avionics, ability to carry R77 plus a limitied selection of guided ground weapons. (didnt mention anything bout anti ship weapons though)
As for mig31s, that would be a great platform. Far from a sniper, as its radar would scream your position hundreds of kms away but still, it was built powerful enough to burn through some jamming. Thing is, in todays almost solely BVR fighting engagements, especially over sea where there's no way to hide from radar, having a really fast interceptor seems like a better idea than having a manouverable dogfighter. Sure, in theory one out of ten Su27s could somehow dodge the missile in the end, but i'd bet more than one out of 10 mig31s could get an additional kill due to greater speed and launching alt it gives to its missiles, not to mention greater situational awareness its radar can give it. (or space for newer updated radars, that mig31 nose space is huge, even compared to su27)
Concerning Meteors, i say forget it. It seems to be a great missile but there's no way europe will sell it. China is 'doomed' to indigenous and russian AAM weapons.