Topic: Caching a Model with Associations

Okay, I have three models: Alpha, Bravo and Charlie...

class Alpha < ActiveRecord::Base
  has_many :bravos
  has_many :charlies

Once an Alpha record is written with the associated Bravo and Charlie records, it will never be modified. However, it will be referenced very heavily for the next 5 minutes by most of the actions in the app. So, I've been looking at caching options...

Page, Action and Fragment caching don't quite meet my needs in this case, since most of the results are highly dynamic based on user input. I also looked at CachedModel, but that doesn't seem the answer either: I don't have the ability right now to run memcache and I absolutely want to cache the associations (the Bravo and Charlie records). Furthermore, I don't really need to cache any other models... just these.

Any suggestions on existing plugins or tools? Or would I be better off writing my own cache manager for this? If I'm better off rolling my own, any suggestions on strategies?