Appropriate wetsuit for Sonoma Coast in July?

Sorry for spamming the boards, guys.  I have a 3mm wetsuit that might be a little bit hot and restrictive for the conditions at Ocean Cove this month.  Here's a link to the one I own:

http://www.nrs.com/product/2213/nrs-rescue-wetsuit

I could just wear it without putting my arms and shoulders in it.  It is possible to get it all the way on when I'm in the water, should that become necessary.  Looks like most people use farmer john suits.  Any of you experienced guys have advice for me? 

Dress for immersion.  In the event of an emergency, the LAST thing you need to be doing is trying to put on the top half of your wetsuit once you've already hit the water & hypothermia has begun.  Not to mention that, in order to do that, you would have to remove your lifejacket.  BAD, BAD idea!  Yes, farmer john is the better way to go if you are planning on wearing a suit or go all out for a drysuit.  FJ can be bought for $80+.  Other alternative is possibly keep it zipped a bit down, depending on where the zipper is located.  Otherwise, clam bake!  I know it sucks, but it's the situation.

Oooh yeah the lifejacket.  Not sure what I was thinking there.  Thanks for the reply!  I think I'll try and find a farmer john.

At least with a FJ, back when I used/had one, you could layer on top of it & then put on the lifejacket.  If it got too hot, you could VERY BRIEFLY, remove the lifejacket to drop layers.  Don't forget to put the lifejacket back on though 

FYI, some used FJ suits (7mm) (and other used wet suits) were on sale at Diver Dan's in Santa Clara for $30 only.

7mm might be an overkill (way too hot) but a good deal for only $30