I would suggest going for the later four leaf 4 seater springs, which transformed my 2012.
I sourced mine from Mulfab, but the dealers should all be able to supply.
Oh and yes it's a diy option, but expect hard work in lining it all up. If you haven't tackled leaf springs before, it may be best not to attempt it yourself.
I'm out of touch with prices but a wild guess......around £450 for the springs and something similar for fitting....maybe!
Scroll right down this post to get a flavour of what's entailed:
http://www.talkmorgan.com/ubbthreads.php/topics/375009/9
