Whilst I don't agree with kitbag that there's no appetite to reconstitute the MPA capability, especially in light of the very embarrassing public exposure of our capability gaps, I do think the point about lack of space on our remaining few operational airfields is very valid.
It's for that reason, combined with the general apathy towards Defence in general and defence depending in particular, that makes me think the politicians will try to do it on the cheap by re-rolling or developing existing capabilities to bolt on the MPA function. I could easily see any of Reaper, Sentinel or Shadow being tweaked to fulfil a basic FIND function, which no doubt would be acceptable to the politicians and enable them to say they were doing something about it, as well as being championed by the platform desks keen to preserve or grow their own bit of capability.
It wouldn't mean a huge infra bill as they look for somewhere to park new platforms, sqns, hangars and msn spt and could probably be done quicker than buying even off the shelf. The seed corn crews could be brought back and integrated into the existing sqns as the Maritime Flt of a MMA capability. Plus, any political uncertainty following the next election that will potentially hit the economy hard, as will a down turn in the 'recovery'. Don't forget, the 'recovery' has been in play for longer than most economic cycles and the commentators are already starting to look out for the next downturn which will likely limit defence spending even further.
All speculation on my part, and I hope I'm wrong and we do it properly first time round. I just can't see it happening with so many other competing demands and a Treasury that doesn't give a damn about the military and defence of the nation.